Hi, GOS-Foundation offers the covenient possibilty to make donations via bank transfer (pretty common here in Europe): https://grapheneos.org/donate#wise
I really like that, because you don't need a credit card, crypto currency nor register a user account or fill out forms with your personal data.
When I briefly checked e.g. Molly, Signal and Accrescent I found no such simple option. Maybe I didn't search their websites long enough. I'd really like to support those developers, too, but I am missing a simple possibility like the one offered by GOS. It's just too complicated, in my opinon, and I'd like to encourage them to follow the example of GOS.