For me, poker is a hobby, so I play when I have such a desire, when I have time for it and when I am in a suitable, good mood. Maybe it's better for my brain to play in the morning, but for me overall it's better to play in the evening.
I like to play poker in the evenings more, often in the evening I am not busy and I am sure that I will have to interrupt the session, besides I am a night owl
Oh, for me, poker in the morning sounds like something scary, I like playing in the evenings much more, because the brain works more actively even after 10 pm