May I ask you to share your experience and advise about how to borrow ETH to buy BTC, please? I'm interested in taking adventage of price action so could be settled off-chain.
It's not always like that. You can try to borrow ethereum through some defi sites like Aave but the problem is, do you have collateral for doing it? i meant you shall have collateral to get approven borrowing ethereum to be used to buy bitcoin.
If you have no collateral and you cannot do it. It's caused by the platform will ask your collateral first before you will be able to borrow ethereum from there.
There are so many lending sites in crypto. You can try to take a look at this article
https://learn.bybit.com/defi/best-crypto-lending-platforms/It gives you lots of lending sites in the crypto, but to be honest, you will be doing a high-risk decision.