So regarding Avengers Assemble 002 Hawkeye's trait:

TRICK SHOOTING: Give Hawkeye a power action to place an Aim token on this card. At the beginning of your turn, if he has 1 or more Aim tokens on this card you may remove them and choose one effect that Hawkeye can use this turn: Improved Targeting: Ignores Elevated Terrain, Improved Targeting: Ignores Outdoor Blocking Terrain, or a locked range value of 14.

It says IT ignores outdoor blocking but this is not found anymore on the latest PAC. So how will it translate to the recent rules?

So, technically the effect does not exist anymore and therefore he would not be able to use it in modern games.

It's not that simple though.

The standard has usually been "use the last version of the effect that did exist/have rules if it's not in the latest rules". In the old rulebook, there used to even be a paragraph to this effect:

But... this paragraph (or anything like it) is absent in newer rules documents, as far as I can tell.

The last version of the rules I can find that have anything about IT: Outdoor Blocking is the 2014 PAC. It does exactly what you would expect.

I would also appeal to the "spirit of the game" rule. Unless WizKids specifically erratas or clarifies that it doesn't work that way anymore (I can't find a ruling to this effect, though they have replaced it with pure IT:Blocking on a couple characters), then I would have it work as intended/understood.

For a translation to the new wording, I would go with:

"Improved Targeting Outdoor Blocking: Lines of fire drawn by this character are not blocked by Outdoor Blocking terrain."

So it's ultimately up to you/the judge, but it's such a straight forward effect that I see no reason to handicap an older figure in the name of "technically".

Finally, a link to a previous thread discussing this ability.

Thanks a lot for that thorough explanation