i don't think much about it. i see ho-oh and i think, "there's ho-oh". it just is what it is.
but there are some exceptions where i strongly associate the pokemon with a certain gender for some reason:
male - darkrai, lugia, zekrom, necrozma, solgaleo, xerneas, cobalion, latios, kyurem
female - lunala, virizion, and what this anon said
>>32232986 minus lake trio and celebi.