To be honest, I don' think Yokai Watch will catch on anywhere else.. : /
This. Just seems like it will be way too Japanese and niche to catch on. Pokemon didn't have that problem since it was able to be fully localised. A lot of Pokemon were based on animals, so stuff that western people will recognise anyway. Yokai will just appear foreign to western audiences. There was the anime too, that was simply better than the Yokai Watch anime (by quite a significant margin as well) and got fully localised too, even the rice balls, I mean... jam donuts
Besides that the things that helped make Pokemon mega popular, handheld gaming, the anime, trading cards etc just don't seem to be as popular with kids as they did back when Pokemon released.