I've been shooting longbows and recurves for more than 50 years now and have never had a problem switching from one to the other. About 80% of the time, I shoot the same longbow, but I might use a different bow in the afternoon sit than I used the same morning. Mostly depends on my stand situation. A short recurve works better in very tight quarters or a blind. Longbow is fine in most other situations. My bows and arrows are all pretty close to the same weight so there's little adjusting to do. Though I prefer a straight grip,i t's no trouble changing to a medium recurve grip. About the only grip I really don't like is a very high wrist recurve grip, but I don't own any bows like that.
I don't buy the argument that sticking with one bow,or one gun, or one anything, will necessarily make you better with it than if you alternate among several. Proper practice is what makes you better.