Hm, what do you mean? Unless it's an Intel thing:

For AM4: The ASUS card (at least the one I'm looking at) is PCIe4 4x4, while APUs only expose PCIe3. Should still work but over PCIe3 with X570. I've been running PCIe3 4x4 cards from other makers on that chipset and did not notice any issues.

For AM5 I don't see why not?

I have not tried but something like this might be what you are looking for? https://aliexpress.com/item/1005005311953959.html

There are bifurcation cards from other makers with other configurations also exposing two m2 slots, if you look around. E.g. https://www.10gtek.com/nvmessdadapterforu.2ssd