You might want to try learning to do it yourself. Translation is one of the best entry points into programming. And Mlem is open source.

Step one: learn a little about git.

Step two: grab a copy here: https://github.com/mlemgroup/mlem

Step three: pour through the text files and figure out how they implemented translation.

Step four: start translating!

Step five: send a pull request to the maintainer, so they can merge your changes in.