How do I recover photos from old iPhone with no iCloud access?

hello! I’m not sure how to explain this properly but hopefully it makes sense. I found two of my old iPhones, I’ve charged one of them up and can see a load of old pictures that I don’t have anywhere else (not on iCloud etc).

The problem is they’re not actually downloaded to the phone, there’s the little exclamation mark in the bottom right to indicate this. I can’t download them to the phone because there isn’t enough storage on the phone for them (it’s a 16gb phone) and I can’t figure out how to transfer them to my windows computer (when I import my pictures they’re not included).

I’m also worried that if I connect the old phone to my iCloud it will wipe all of the old pictures and replace everything with my most up to date iCloud back up. The phone keeps prompting me to sign in to iCloud but it's still using my old Apple ID email that I changed years ago and I can't access that old email address anyway.

If anyone could tell me what to do that would be appreciated!

[Re-Titled by Moderator]