Yes, since the Chandelure would be coded with a Hidden Ability spot and S/M/US/UM has Infiltrator in that spot, its Ability would change to match that spot. :P
However, it is impossible to get a Chandelure with Shadow Tag in gen 5 (as you stated) due to it not being released; so, Pokémon Bank would probably block it for having an unavailable ability, and thus preventing you from transferring the Chandelure. :P
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Hope I Helped!