You can't really impose strong non competes on interns. You don't show them the good stuff either. Just enough to get/give an impression for later recruiting.
As mentioned in comments, it's pretty rare to give a strong non compete to interns.
But interns aside, the whole industry is built around these competes, so mechanism are in place to circumvent them.
Some HF will happily buyback the non compete, some will offer a welcome bonus to compensate, some will be ready to wait, some will make an offside deal with the departing company, etc.
Do you have a list/advice to find them? I only found a few with offices in Switzerland, and not being in the industry I don't fully trust my judgement of what is "reputable"