Hello, 
I have two projects (A, B) on the Jira Cloud with Exalate plugin in Visual mode, I set up all fields which I need to be synchronized and now I need to set up condition for synchronizing comments. From project A should be synchronized all comments to project B, but from project B I need to synchronize only comments which contains specific string (lets say "SYNC:"). 
I found this older topic, but it wasnt really helpful, only thing which worked was script for hiding string, I suppose because it was meant for two Jira instances. 

Possibility to sync Jira comments only if the start with a specific string

Thanks