What are wrapped beacon ETH and wrapped BTC?

I was researching some stable coins and came across these two. As per my understanding the underlying securities here are ETH and BTC respectively but they are in the form of stable coins. But if stable coins are meant to be more stable and less volatile, then how can you expect these two to be less volatile since the underlying are not?

And are these two stable coins seen as alternative investments to the traditional coins or do they have a different purpose? Would really appreciate some help in understanding these.