We don't have synonyms for synchs yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are synch, synths and syncs.
(v) :
Alternative spelling of sync. [(informal) To synchronize, especially in the senses of data synchronization, time synchronization, or synchronizing music with video.]
(v) :
Alternative spelling of sync. [(informal) To synchronize, especially in the senses of data synchronization, time synchronization, or synchronizing music with video.]