G1 in the US had some early books, some cassettes, and a MLP Club - but pretty sure no comics.
The US-centric nature of the cartoon thing is also interesting. And very true, though I never thought about it.
I think the UK had 12 or so G2 comics. I used to have them all but sold them...sister may still have some.
France definitely had more though, and it is true that translated comics existed in Europe during G1. I've seen Finnish ones as well as German...I have some of the German ones because they have amazing photo ads for ponies like Nightlight etc in them
G2 probably just didn't need animation to be popular. When I think about it, while there were a number of kids' shows when I was small that were made in the UK, I don't remember any of them being actively linked to toy lines in the way US ones were. It doesn't mean toys didn't exist for some of them - just that it wasn't the be all and end all.
Raggy Dolls may be the main exception to this..? My sister had Hifi so I remember it was merchandised up pretty big.