I know that using a CEX is the easiest and safest and cheapest however you would think that by now there would of been a solution already to bridge between the 2 largest crypto blockchains out there.
Probably still in the making. There are some bridges before that I encoutered of but it seems its like an atomic swap version or crosshain. Bridging is something like sensitive of. As far as I know avalanche develop a bridge of bitcoin directly to avax network bitcoin but not of eth. But you could already converted that unit into eth and bridge to common L1 after that.