The basic gist is if you need to trust someone has kept their keys secure, send them some BTC.
Generally speaking the sender doesn't care about what the receiver is doing with their wallet. They could be using a very safe one or a custodial wallet (that doesn't let the balance stay in the address anyways) or a very insecure one.
So the real question is what is the application of this project of yours since senders don't care about receiver's security?