Wait, hetalia is BL? *Checks the tags on danbooru*
Oh God...
I guess that's what I get for only watching the anime. OTL
The original webcomic IIRC wasn't so heavy on the yaoi subtext early on. It was teased though but nothing too blatant , sometime down the road though the author decided to humor the yaoi fans by turning it up.
I'm not too sure though I don't follow it that much. I do like some of the girls though there. Hungary and Belarus being particular favorites. Though I do like Prussia.