I’ve never played a Vampire Survivors clone before, and I see why the genre is so popular!
The version I downloaded doesn’t seem to have a cap on how many items of a type you can choose, and at some point, some items no longer seem have an description or an effect attached to them.
While I don’t have a full overview of what items are affected in what way, I am reasonably certain that the stopwatch retains its effect.
In unrelated news, the succubus seems to be immortal. I’m not sure if this is a bug or intended as a way to limit how long a game can last.