
Since the only in-game Hud mod I've seen was that "Another Hud" (i think that's what it was called) mod, but seems to be removed because it was just a test mod and wasn't optimised at all, but the person who made it did say in the description that supposedly one was being developed, but nothing seems to come out of that as of now
now, i know we will be getting a UI update next month and it more than likely stopped anything related to changing the in-game hud, but it would be nice to know

It is possible to create a completely different hud but you have to take into consideration that you are not in full control, you can change the blueprint stuff but there are a lot of the functionality done in c++. Take for example, the health opacity change when you mask. It is done from c++ side. So, you need to make sure you have something it can set opacity on. Also since you won't be notified of such change, you will have to do polling, i.e. checking every period of time if the changed happened or not. This will slightly slow things down, lowering your fps.
But in general, it is very possible to make a HUD based on a different design. You just need someone to invest time in it. A lot of modders dropped from the game and it is not clear till when.
heard of RinoHUD on nexus?
yes, i've already got that, but it just builds onto it the vanilla hud rather than it be it's on kind of hud if you get what i mean