Yes, but that wouldn't count as ethics. You wouldn't want a Universal Law that one guy gets the harem, and everyone else is a slave, because you wouldn't want to be a slave, and you probably would be.

If there are a lot of similar agents in similar positions, Kantian ethics works, no matter what their goals. For example, theft may appear to have positive expected value - assuming you're selfish - but it has positive expected value for lots of people, and if they all stole the economy would collapse.

OTOH, if you are in an unusual position, the Categorical Imperative only has force if you take it as axiomatic.

This is brought out in Rawls' version of Kantian ethics: you pretend to yourself that you are behind a veil that prevents you knowing what role in society you are going to have, and choose rules that you would want to have if you were to enter society at random.

That's not a version of Kantian ethics, it's a hack for designing a society without privileging yourself. If you're selfish, it's a bad idea.