As a parent, my main concern with Pokemon is that it would probably lead to other forms of japanese anime and manga, which may promote anti -Catholic agendas.
You're being a little ridiculous here. First, you're making an unwarranted assumption that engaging in a morally-neutral activity will lead to others simply because of its nation of origin. Secondly, you are assuming other activities from that nation are automatically anti-Catholic. Taken to its logical conclusion, you would have to forbid you're children from engaging in any morally-neutral activity.
Ought we prevent children from reading Tolkien, as it may lead them to other English literature that is Protestant and anti-Catholic? Do we prevent children from eating Chinese food as it may lead them into Maoism? Do we prevent children form playing golf as it may lead them to Scottish Fɾҽҽmαsσɳɾყ?
Tolkien was Catholic, so C.S. Lewis probably would have worked better for your example. And the golf thing is just silly. However, your point was still clearly made and not without merit, but is, perhaps, a bit too cavalierly dismissive of some facets of Japanese culture that ought to be of real concern to Catholic parents.
I've had no small exposure to anime and manga from my youth. Some of it is perfectly harmless. I don't think Astro Boy, Speed Racer or Gigantor pose any kind of immanent spiritual or moral threat to anyone. However, Japan, despite its ancient and comparatively noble culture, is still a pagan nation with certain moral pathologies that Catholic parents should be aware of. sɛҳuąƖ perversity and pornography, for instance, are rampant in Japan (though I would blame this more on postwar American influence than anything else) and that occasionally trickles down into otherwise innocuous cartoons and comics.
As to anti-Catholicism - I remember seeing more than a few sacreligious and blasphemous things in anime and manga, though it usually seemed to be borne of ignorance than the kind of willful, intentional maliciousness we see in the Jew-controlled media of the West. The Japanese have a fascination with Catholic imagery that is rooted in shallow exoticism, and is therefore pretty woefully ignorant (much like the average westerner interested in Buddhism, Yoga, etc.) That said, blasphemy is still blasphemy, regardless of intent.
In short, Catholic parents shouldn't let their children view anything that they (the parents) have not screened first. And, for the reasons given above, they should be particularly wary of anime and manga.