Make sure your running at least v3.0.3 of Modmail. in your config.ini file, make a new line and add:

plugins[] = npm:MMPlugins/HexedHelp
extraIntents[] = guildMessageReactions

Stop your bot.
Run npm install eris-pagination in the bots directory.

Restart your bot!
If you'd like to add a language add this line of text to the config file. And copy the contents of en.json and modify it to your language.

lang = filename

And that's it! Use [prefix]help (by default, your prefix is !) and watch the magic!

English - en
German - de