> I send stablecoins to family member (worth noting this would be difficult to do in FIAT due to the amount) and when he pays me back I can then withdraw my $TOKEN.

While you're on your high horse about the taxes comment, you should know that in the US what you're describing here is illegal. You can't give someone an interest-free loan and have neither party pay taxes on it. Your options are roughly either to classify it as a gift or structure it like an actual loan, with a minimum acceptable rate published by the IRS each month. https://www.lindsayandbrownell.com/beware-of-the-interest-fr...