My favorite open source game is by far Ring Racers

Regular colemak user here, I have found the simplest thing to do is use the langmap option to rebind every function of hjkl to neio.

To try it out or add it to your init.vim config, run set langmap=hjklHJKLneioNEIO;neioNEIOhjklHJKL

If you have an init.lua config, add vim.opt.langmap = 'hjklHJKLneioNEIO;neioNEIOhjklHJKL'

It will rebind your motion in all modes and their shortcuts, so you don't have to spend any time mapping everything individually. However, it doesn't remap things in some extensions like which-key which is a huge pain to the point that I have just stopped using the extension entirely instead of trying to figure out all the mappings for a seamless experience.

You should look into TF2 Classic

Switching keyboard layouts is really hard it can take a lot of time to adjust. I haven't been using it for very long (only like a year and a half) but there are lots of users who say it is well worth it in the long run. If you're feeling f-ed about your new layout, I recommend trying to learn it as a side project over time, rather than making your whole setup use it. Stick with what you know for important stuff and use something like colemak academy until you are proficient enough to make the switch.