Need some clarity on Underwater rules and Natural weapons

Do unarmed strikes have disadvantage if you don't have a swim speed. Now considering it specifically highlights weapons of which a unarmed stike is not. Also are natural weapons considered unarmed strikes and there for possibly not affected by the underwater rule aswell. Thank you to anyone who can help me with this.

I agree with wagnarokkr.

Just considering the 2024 rules, "natural weapon" is not a term and doesn't have mechanical importance in the game. So far, I've only found "natural weapon" in the Alter Self spell, but again, it's related to Unarmed Strike. It would have been nice if even in that spell they hadn't used those cursed words.

EDIT: tooltip and wording.