Do Wild Cards Count as being on the same team as a character who has a standard team ability like X-men or Fantastic four for Briliant Tact. Purposes?

For B. Tactitain (sp) the piece needs to have the symbol on their base. The wildcards just copy the ability of another fig, they don't change theirs.
I think....

This is incorrect for Brilliant Tactician. BT specifies that the characters must have the same team ability, which a wildcard or T-bolter could have (depending on what it is copying).

However, other feats and BFC (such as Inspiring Command or Assembled) do rely on team symbol, which never changes.

So look for those two words:
team ability = ok to use with wildcard/t-bolts
team symbol = not ok to use with wildcards/tbolts (unless the wildcard or t-bolt is the appropriate symbol, of course)