Yeah I mean in a lot of strips that people use as evidence for England there’s similar evidence for America there as well. We see America blushing over him multiple points, and there is also stuff like the fact that England is the only person we ever see him get legitimately and seriously touched over. Heck he cries happy tears because England gave him a gift. He also asked him for Valentine’s Chocolate so…
There is of course Hetaween as well, where the whole twitter follower thing was revealed by Hima to ‘just be an excuse’ and he would have found a way to get England to do it anyway. The leadup of that, the paneling, the delays, etc. was certainly framed like a ‘love confession’ imo.
And I think it’s important to note that USUK is featured in Buon San Valentino with two (imo) definitively romantic pairs (GerIta and AusHun).
You could argue forward and backward whether it’s definitively romantic or not, but to be honest there’s more stuff there for USUK than there is for some pairings that are widely considered canon in other fandoms.
How about that cyclical fandom cycle.
Guess who read Hetalia fan fic last night with insomnia.