I think it's safe to say this rule would continue to apply to guards, at least.
Regarding leaders, it's a little more murky. The Battle of the Guard special rules say that a leader blocks LoS and movement and may be targeted by any figure. After the influence effect is revealed, leaders are to be treated as either heroes or monsters, depending.
At the very least, this means figures of the same type can no longer target the leader with attacks, so at least part of the Battle of the Guards rules are being overwritten. Of course, nothing actually says Battle of the Guards ceases to apply, so whether the remaining effects that are not specifically contradicted continue to apply or not is unclear.
I'd say it's a good one to ask FFG.