Hi, I would like to suggest KDE to accepting Monero (and probably other cryptocurrencies as well) for donations. Because Linux community and privacy community are close to each other so KDE can benefit by accepting anonymous payments.
Also accepting Monero will be much cheaper and easier than accepting card payments.
As stated on KDE e.V.'s website:
KDE e.V. does not accept donations of “crypto” coins: Bitcoin, Etherium, Litecoin, Dogecoin and all the others. The tax regime that covers German not-for-profit associations considers those coins a form of speculation which would endanger our status – so regretfully you cannot donate them directly. Cash out and then use a traditional method to donate.