> According to the taxman's website [0] you need to be a "liberal enterprise". Not sure what exactly that means, but I'd be surprised there's no form of bureaucracy involved. I think you need to have at least a "micro enterprise".
We are not referring to the same thing, I think. You're looking at the tax for corporates when I'm looking at individuals [0]. The key seems to be that it's has to be exceptional and not regular. I'd still double-check on a case by case basis with the tax bureau before going ahead, but I've found them to be helpful in the past.
It does make sense for niches like these to exist, otherwise you'd end up having to setup a legal entity before being on the receiving end of a transaction as an individual.
[0] https://www.impots.gouv.fr/sites/default/files/media/1_metie...