More to the point curved end bracelets, I have just realised watch bracelet manufacturers who sell curved end bracelets do it wrong. I could own a 36mm watch and you may own a 50mm watch. Though both are circular and wear a 20mm strap. The curved end might not fit.
A possible solid would be the watch company’s include/offer curved end links for their products.
Because every watch is different, there is no standard set of fitted end lugs - you need to get them specific to your watch. Not only would you need the width and radius of the curve of the endlink to match, but also the height, the shape of the back where it sits against the case, the shape of the front to match the lug design, the finishes and more.
Because of this you just don’t get aftermarket bracelets with fitted end links for most watches - some brands may have them available as an option, and there are a few third party options available for some very popular watch models like the Seiko SKX, but if the manufacturer doesn’t make one, you are out of luck for most brands.
What is available as an option would be a bracelet with a straight end link - this means as long as you get a bracelet with the correct lug width (usually 18/20/22mm) it will fit, but there will be gaps between the bracelet and case.