You have to be careful, especially with the cheap watch winders. They *will* over-wind the watch ... even watches with "overwind protection" ... they'll keep the spring wound tight for the duration of their ride. Reversing direction is not enough, you need to be able to adjust the period of when it'll wind, and for how long to accommodate the specific watch.
For one or two watches, it's not a big deal, as mentioned, just manually wind the watch every day or two. I have more than one or two watches, most of them are autos.
"Good" winders are over a thousand dollars. Good winders for a lot of watches are several thousand dollars (I've seen some for US$14,000.00).
When you're talking about watches that are US$20K - $200K, a couple thousand for a good winder is a good investment. When you start adding "complications" (features) to the watch, it can take a while to get everything re-set after it totally unwinds. So it's also a great convenience.
The watches are not harmed by letting them stay un-wound, but they should still be moved occasionally to keep the lubricants well-distributed.
I tried a cheap winder ($200.00), six months later I had the four watches that were riding on it in for new springs and overhauls .. they were all dead (a B&M, Bell & Ross, Brietling Navi, and a Rolex DateJust).
Be careful ...
Good Luck & Happy New Year
Scott