I am currently subscribed to Box of Manga and enjoy it. You aren’t going to love every manga you receive, but it does expose you to unique series. Also, a big part of learning a language is exposure to material in the target language, this is a great legal reasonably priced option for reading practice. Personally I’m a beginner level, so I receive the manga faster than I read through them, but I do love it whenever I receive a box in the mail.
Also, if you are going for reading practice, I would check out the Zebrack website, they currently have free to read manga series due to COVID 19.