I haven't touched Haxe but I still find it interesting, are there any downsides or trade-offs I should be aware off? Maybe something that bothers you that needs a workaround?
Haxe compiles to a lot of languages. Some of those language targets are better maintained than others. I've definitely had situations where some usage of esoteric Haxe features (like, deep/complex generics alongside runtime polymorphism) compiled fine to one target but compiled to invalid or incorrect code on another.
(Interestingly, in my experience the C++ target is rock solid. Though that experience is from many years ago.)
In any case, the best source for known compiler bugs is always gonna be GitHub:
Haxe makes it really easy to get started and get a feel for things, just have a go!
I found the opposite with Typescript, where it seemed like I had to already be a javascript developer to use it.
