The Handoff, Back to Base, Change of Plans, After Him, Tracking Zhijie, Conveyor Belt Bedlam, Double Back, and Main Pillar Maintenance are quests in Chapter 1, "Wutai's Finest", of "Episode INTERmission" in Final Fantasy VII Remake. "Tracking Zhijie" has the subquests Conveyor Belt Bedlam and Double Back. As Yuffie Kisaragi becomes acquainted with the Sector 7 slums, she is joined by Sonon Kusakabe, as they work with Avalanche to achieve their goal of stealing materia from the Shinra Building.
Walkthrough[]
Talking to Nayo outside the Avalanche base and selecting "Yes" when she asks if Yuffie is ready will continue the quest. However, before doing so, this is the opportune moment to complete the three sidequests, "Chadley's Research", "Mastering Fort Condor", and "The Happy Turtle Ad Campaign" first. Doing so will earn a number of powerful materia that can be equipped to both characters.
After talking to Nayo, follow her to the objective. A cutscene commences along the way, after which, continue to follow her to the Municipal Storage Area. Talk to her in front of the gate, and then enter to fight a group of Corneo Lackeys. They are weak to 
Fire, making Fire Ninjutsu ideal against them, while crowd-control abilities such as Windstorm are also useful. Defeating them earns a chthonian armlet, after which, follow Nayo again into a warehouse, where another cutscene commences as the IDs are acquired.
Once the IDs are obtained, return to Avalanche's base, grabbing a kindred cord from the treasure chest on the way. Halfway along the path, a short cutscene commences, and the new objective is to follow Nayo to the Sector 7 Pillar. Upon reaching it, following a cutscene, run after Zhijie to the edge of the Sector 7 Undercity Station, and through to the Train Graveyard Entrance. Through here, on the right, the Indurate Staff for Sonon can be obtained. After another cutscene, descend the pole to the Shipping Facility Connecting Passage.
Shipping Facility.
In the Shipping Facility, follow the linear path forward to chase Zhijie. Cripshays are fought on the way, and are weak to 
Ice and thus can be defeated with Ice Ninjutsu fairly quickly. At the conveyor belt bridge, use Throw to deactivate the conveyor belts on the other side, follow the path straight ahead down to more cripshays and a treasure chest with a Sweeper (Ranged) Fort Condor unit, then take the pole upwards to the upper area. This will begin a battle with an elite security officer and a standard security officer, both of which are weak to fire and can be defeated with Fire Ninjutsu and crowd-control abilities.
Prayer materia.
Once the officers are defeated, the path on the upper level forks. First, head north to fight two lesser drakes, weak to 
Wind, and best defeated with Throw + Windstorm or spells. The 
Prayer Materia can be found after defeating them, following which the objective should be followed by heading south. Yuffie will remark the conveyor belt needs to be deactivated by hitting a switch, which can be found on back down the path, on the center of Ward 3 on the upper level. Wait for the boxes to not obstruct the line of sight to it, and Throw to deactivate it. Continue to follow Zhijie, and interact with the device to operate the conveyor belt.
Steel Reaper.
After continuing to follow Zhijie, Yuffie will fall to the lower level after a cutscene. Continue forward, where a horned cripshay is fought, an enemy weak to ice but more durable than previous enemies. Throw and use Ice Ninjutsu, damaging it while remaining a distance from it, and when it summons other cripshays, use Windstorm to deal area-of-effect damage against them. A Gozu drive is then obtained for defeating it, which can be useful in combination with the cthonian armlet armor to deal damage based on the equipper's HP. Take the pole up, and the Steel Reaper can be found in a purple chest, which has high 
Attack Power and teaches the powerful Banishment ability that deals elemental damage based on the Elemental Ninjutsu element and the ATB spent on other commands.
Yuffie wall-running.
Proceeding forward after the purple chest leads to a short cutscene, followed by a battle with another elite security officer and an elite grenadier; the same tactics as used on the previous security officers apply against both. Hit the conveyor belt switch next and proceed forward to the Storage Depot. Run along the wall and climb up it to the top, then hit the conveyor belt switch atop the platform and Throw at the conveyor switch on the opposite platform to create a path across. The Toxirats that appear can be defeated with standard abilities, after which the player can pick up the Assassin Board III Fort Condor board 
from a chest in Storage Depot - Upper Level. The more challenging wrath hound is fought, which can be defeated with ice-elemental attacks, and it is best to use Throw and attack from a distance due to its powerful melee attack, Throat Clamp, which can stun a character and deal heavy damage. Keep a distance and use Ice Ninjutsu with a charged Banishment to defeat it.
After defeating the Wrath Hound, hit the switch to move the wall to run across to a set of platforms, then at the top of them, Throw to hit the same switch and move the wall back and create a path forward. Wayward wolves are fought here, which are similar to the wrath hound but less durable; the same strategies apply, and it is important to dodge many of their hard-hitting attacks. After beating them, Throw the star to hit the switch opposite, climb the wall to left to defeat some gorgers (same tactics apply as against the cripshays) and grab a treasure chest, then climb the wall right to a lower platform, and Throw to the same switch to create a wall path. Climb the wall up to a top platform and Throwing to the same switch creates a path to the platform with the switch on, where an 
Elemental Materia orb is found here, while continuing to the top-right platform and Throwing back to the switch creates a path down to the Temporary Storage Area lower level, the Waste Disposal Area.
Breaking boxes from a distance.
At the Waste Disposal Area, proceeding forward will lead to a brief cutscene, where a levrikon is fought. This enemy is weak to both fire and ice, meaning using either Ninjutsu is effective. Much like previous larger enemies, it is best to use Throw and remaining a distance from it while using Ninjutsu-infused attacks. Defeating it will earn a Mezu drive, which is similar to the Gozu drive but instead works based on MP. Continue along the path and take the ladder up. Smash the box on the left to obtain a note from Zhijie, and then operate the conveyor belt. A number of boxes can be broken along the way for items, and at the end is a linear path to Perimeter Wall. A 
Magic Up Materia can be found just to the left 
, and on the right, the path continues into Main Pillar Maintenance. This commences the next quest, "Save Zhijie".
Hard mode tips[]
Against Corneo Lackeys and Shinra soldiers, pairing 
Fire Materia with Elemental Materia can be helpful for damage, along with using Fire Ninjutsu, Synergized Art of War, and Fiery Banishment. Against the wolves and later enemies, Icy Banishment and Ice Materia with elemental are better choices. For powerful enemies such as the Wrath Hound, it is crucial to, as well as using Brumal Form for frequent dodging, use a mix of Throw and Ninjutsu to attack from range and Synergized Windstorm to keep them at a good distance.
Assassin board III for Fort Condor is obtained in a treasure chest in Storage Depot - Upper Level Ward 2, and is crucial to pick up to complete "Mastering Fort Condor" in hard mode. Minibosses such as the levrikon also drop SP books when defeated.