I just bought the hexblade as a class so i could make use of the hex weapon feature in homebrew classes, but it seems i'm still unable to add it on the character sheet whenever i make a subclass based on it. Is there any way to get acces to the charisma based attacks on anything that isn't hexblade?

You need to add a class feature named “Hex Warrior” to your subclass.

Doing that makes it impossible to share the subclass because it becomes too similar to the hexblade to share with the community, even though it is the only class feature that is remotely alike.

I figured out it needs to be the exact same feature as "Hex Warrior", down to the same proficiencies and bonuses to be able to make a weapon a hex weapon on the character sheet. Buying access to the class doesn't do anything for homebrew and doesn't allow you to make a class with similar features. I assume this is so the plebeians that haven't paid for the content can't magically get access to any of the extra features through homebrew.

Nope, just naming a feature “Hex Warrior” does the trick. You need the same Modifiers to add the proficiencies, but the Hex Weapon functionality is tied directly to the name of the feature, it doesn’t even look at the description at all. You probably just experienced some system lag, or delayed caching is all.

I'll have another try and re-check later to account for caching, thanks

It was indeed caching that made me unable to set a hex weapon, it seems to work now. Is there also a way to actually share homebrew with the "Hex Warrior" feature or is that just off limits?

If you leave the feature completely blank and have nothing else’s similar to the Hexblade it should be publishable. But don’t publish it right away. Take a few months to thoroughly playtest and edit your homebrew so you know it A) works properly, B) is balanced, and C) has no typos or anything. Once you publish it you cannot edit it anymore.

Thank you for your time, I'll get it all sorted out.

Happy to help.