Hi Branden, Kind of a facepalm moment there, I realized that the .hcode request don't work since my source file is encoded in UTF-8. Making a separate file with the requests, encoded in latin2, and sourcing it in the document allowed me to fully utilize the hyphenation pattern file.
So! I started work on preparing the localization file. The pattern file should also be formatted somehow, right? Or can we use it as-is? I still have to figure some stuff out with building groff and the exact workflow of contribution, but hopefully Hungarian support can soon be part of groff, which fills my heart with joy! If I have any questions regarding the afformentioned contribution process, is it okay to send you an email? Thanks for all the help! Best regards, Gergő