It used to be possible to do this, and it is even documented here: https://lingualibre.org/wiki/Help:Create_your_own_lists

Now there seem that there's no direct option to do that, isn't it?

Actually, this feature dissapeared in the new version of the Lingua Libre website. So the documentation should be updated. Meanwhile, this task remains open to ask for this feature comes back.

If a list of lexemes in plain text is given, will the bot upload the audio?

You can still copy a list of words in plain text; the Record Wizard is able to parse them if words are separated by the # character. Concerning Lingua Libre Bot, it seems it does not add anymore pronunciations on Lexeme since some time. Currently there is noone to debug or restart the bot so Lingua Libre Bot will probably not work in the coming weeks (months?).

That's say, in normal time, the answer to your question is yes.

My concern was the second one. We are trying to make a lexeme pronunciation edit-a-thon (suggestion?) but if the bot is not working, it doesn't make sense at all.

Hmm makes sense. That's said, the code of the bot is public so even if the official bot is not running you can run your own on your server

Thanks! This can be interesting, though I think we'll wait till Lingua Libre adds the posibility to find random lexemes.