For now the closest coin to next eth is bnb. Bnb became the third popular coin after they decided to have their own blockchain. We know the usage on the binance exchange is the biggest. so they can easily get their customers. It is proven by many ico projects that use the binance platform.
BNB easily gets exposure from their service, and may people already trusted them as a platform, that's why their exchange is also big and seeing other similar coins i think BNB could easily be the most potential coin for replacing ETH, because their BSC also so popular among many new projects even before many people already switched to BSC because ETH gas was too high, and I think it's fair to say that oly BNB have the potential.