Just because there are hints of America doesn't mean it is based in America. I'm sure GameFreak acknowledge that they have a wide USA fanbase, that's reason enough to include things that related to them such as the a-football players (A sport which if also played worldwide -.-).
The Eagle can be put down to coincidence, it was time for an eagle like Pokémon and the colours happen to be similar. Strangly you seem to ignore the fact the bird also has the colour yellow. If it was plastered in stars and stripes I might give it to you, but no it's not. Giving it a 'native American headdress' just gives it a certain character, which they picked due to its natural habitat and location - like they do with many other Pokémon.
So everything American can be "put down to coincidence," but the second there's something Half-Chinese it single-handedly proves the game is in Shanghai?
There is still
no reason for them to add an American Football player in any other country than America. They never added one in all the years Pokémon was set in Japan, did they?
If the Eagle wasn't supposed to American, why
would it be wearing a headdress, and just so happen to be red, white, and blue, one trivial yellow band aside?
Yes, it's understandable that alone these things may appear to be coincidences, but the point is that there is more than one, and when they add up, it's only reasonable to think, "Oh, hey, why would they put all these American "references" in a game set in China."
You say they picked the themes of the eagle thanks to its natural habitat and location, America. So why is this bird so far outside its natural habitat that it is apparently living in China?
As far as geography goes, they both look a lot like Isshu. Though I think you'll find that considering my artist's rendition, and knowing that Isshu is in-fact an
artist's rendition itself, one would assume since they look so similar there has been some inspiration there.
Taoism per se is not a large part of Black and White. There is no specific reference to the religion.
What we do see references to is old vs new, nature vs technology, etc. which the West may not have names for, but experiences just as much as any Eastern country including China.
Even Yin-Yang is not nearly enough to prove links to Taoism and China, because just about everybody on the planet knows what that theory is.
But I'm calling that more people will simply disregard this and say I'm starting fights (which I'm clearly not, I have just as much right to voice my opinion as anybody else does), because they've yet to find a way to actually argue any of these points. I may be cold, but I'm at least logical.