So you mean to have the watch's timing adjusted to "perfection" by a technician. Fair enough .. now, once the back is off the replica watch, any jeweler could plainly see that it's powered by an ETA (Swiss or clone) movement .. so to answer your question YES it will be noticed.
My advice to you is to wear the watch for two months until the movement settles. Only then can you know it's true accuracy, and if it requires adjustment.
Once you've done this, send the watch by post to the nearest forum-trusted technician.