Transfers any increase in limit gauge to allies. Your own limit gauge will no longer fill.
Description
Limit support materia is a 
Complete Materia in Final Fantasy VII Rebirth. It causes the holder's limit gauge buildup to be applied entirely to their allies rather than their own.
Obtained[]
Limit support materia is bought from Chadley's Materia Development for 15 Meridian Ocean data points. This becomes available after defeating the boss at the end of the protorelics sidequest.
Use[]
Limit support materia will cause the party member to gain no limit gauge increase, but rather give it to their allies. This can be very helpful when used on a party member whose limit breaks will not serve as the party's source of damage or a key role in the player's strategy (such as a party member who is not used as a source of damage output, or one whose limit level cannot be increased by the synergy abilities of the current party composition).
Limit support can also be used in conjunction with 
Limit Siphon Materia on another party member, to allow the party member to use their limit break more often (as they will only need to siphon from one party member and not two), allowing it to be a major source of damage output in battle.