Trusting that someone doing something markedly unusual is "handling it somehow" is a great way to get some ugly surprises later. Companies do things wrong all the time and in many cases you can find yourself liable for their mistakes/abuses in some way or another. Sometimes at great cost. Obviously, you need to trust every employer/client to some degree, but you'll benefit yourself by developing a sense for what smells fishy.

Unregistered, anonymous work in a world of borders, worker protections, and taxes smells like the dumpster behind a Red Lobster. You don't have to rule out an opportunity that interests you, but do be careful!