In the description for Combat Master it implies weapons for this talent to work.

So would you allow this to work in unarmed combat?

Or would a character have to take Unarmed Warrior to be able to use Combat Master?

Or you wouldn't allow Combat Master for unarmed combat?

Me, I would lean to the character needing Unarmed Warrior to be able to use Combat Master.

What do you think?

Terminology mistake seems to have happened here. It's not just hand-to-hand combat ie unarmed combat , where you can use this but in melee combat ie swords, knifes, unarmed etc .

So you wouldn't need to have Unarmed Warrior talent before choosing this.