Both have blatant weaknesses that are easy to exploit.
Yasuo must push the wave to charge his abilities. He does not have the option to play safe. Outpush him and harass for CS or let him push to your tower to make him an easy kill for your jungler. Side step the tornado. He gets a visual effect and makes an audio cue when it's charged, so you have no excuse if you don't know it's coming.
Pyke has no waveclear and cannot protect his carry in any fashion. He only sets up kills and trades. Push the wave and harass his carry so you always have priority. That way, the marksman can't move up to capitalize on anything Pyke does and Pyke can't just go roam. He can't help his carry push the lane back out and has trouble landing skillshots past the minions while under tower. He'll just heal any poke, so focus on attacking the carry and minions, not him. In teamfights and skirmishes, focus Pyke down first so he can't clean up with his execute.