I would like for my game to feature the ability to synchronize a character with another party member to match ATB speeds, share certain skills, and unlock special "Sync Attacks". I have a theory that this may be possible through auto-passive states and eventing, but I've no actual idea if it'll work and no real idea how to do it even if it could. This feature would be similar to certain titles in the "Tales of" series in which 2 party members can "link" to use special attacks when in overlimit.
I would like for the ability to be a battle only function, unless a certain item is worn or a certain point in the story. For example, character A can only sync with character B in battle. After chapter x, or if x item is worn, a custom scene is made specifically for presetting Synchronizations. (The custom scene is optional honestly, I don't need it but would like it.) Another option might be to let the synchronization persist through battles, so that it only de-syncs if you manually do it or have no one to sync with.