@Danceswithwhippets
A man's point of view here.
I don't think it's odd at all. Not a red flag in sight.
I would see it as a kind of compliment -he likes what you are wearing in the photos, they're your normal clothes. It's not a creepy request for latex and no knickers on a first date!
It is probably a language/cultural thing on his part -you mention that he's Polish.
But if you're not comfortable in being to be told what to wear on a first date, just wear whatever you like and don't mention it.
You say you've got on very well -don't waste the chance of meeting what may be a nice man. Good luck and report back!
Keep in mind that pretty much everybody here is saying that what he has said is creepy/red flag/run away, OP!/controlling etc. Given that you're in the very tiny minority (in fact you might
be the minority) who thinks that what he's said is fine, you might want to rethink your views, as all of those terms could be used to describe them, too.
ie, your post was creepy/red flag/run away from this man, etc.
Ask yourself why you think it's ok to come in amongst a group of women who are all saying 'Ew!', announce your penis ownership, and then tell them that 'actually, girls, you're getting this all wrong.'
It's not a creepy request for latex and no knickers on a first date
Asking a woman to wear something specific is, except in very specific circumstances, a creepy request. If you think it has to be about underwear, you are very, very sadly misguided.