I actually need ram and MB to fit with the 13600k. Ideally
If you're that focused on idle power consumption then I'd suggest you look for motherboards that have low idle power. Historically, that was usually ASRock and ITX, but I don't know much about the current boards idle power. Typically, high-end boards with more features can use considerably more power than lower-end boards, though I wouldn't want to go too low if you're running a 13600K.
You may also want to be aware that RAM speed can impact idle power too, though again, I can't give you any information on this gen.
This is one of the forum threads I would look at and NAS forums can be good sources too.