When traveling, I use a 20W USB-C iPad charger for my 14" M1 Pro. Small, and is plenty for overnight charging. Charges 20% to 100% in about 4 hours.
Doubles up for charging my iPad and phone (obviously not simultaneously), so I only carry this single small charger and a couple of cables.
Yes, I think so, to some (unknown) extent. Emphasis on the word "think." I don't claim to know for sure. But here is a reference so it is not just a random ignorant opinion with no basis: