If I don’t need triggers, how can I remove them from synchronization process?

If an option "Trigger-based sync" at the Customization stage is checked, synchronizer creates subsidiary table to store changes in the source database and three triggers which help catching modifications. To delete triggers including "History_store" table, just uncheck "Trigger-based sync" option and commit the session.

Your source database will be cleaned up from all subsidiary data right after session closure.