Paypal and Venmo - Never put anything in the notes that could be read as "hobby" related.
Cashapp - Same, but the option that allows for the most anonymity
Pre-paid cards are the most anonymous, given you pay cash only for them.
Not as familiar with Amazon, but also be smart with what you put in the notes.
In short
1 Pre-paid cards
2 Cashapp
3 Amazon
4 Paypal
5 Venmo (owned by PayPal, but requires you to make your settings private otherwise your transactions post like a social media feed)
*Amazon may be safer, but I'm unfamiliar (also make sure your settings are private and lock down your personal information)
As someone who is banned for life from PP & V....be careful using those two. There is good advice in this thread. CA, in my opinion is the best!
Also, be careful with Amazon gifts as guys are known to reverse the transaction. Not saying all will, but, make sure it's gone all the way through before anything. Ask for confirmation from him!
This is a very informative thread. :-)