[TFuture](API\Runtime\Core\Async\TFuture)< [TOptional](API\Runtime\Core\IO\TOptional)< [FConcertSyncTransactionEvent](API\Plugins\ConcertSyncCore\FConcertSyncTransactionEvent) > > GetTransactionEvent ( const [FConcertSessionActivity](API\Plugins\ConcertSyncCore\FConcertSessionActivity) & Activity ) const