Im a little out of touch with giants, when a giant has earthbound what exactly does it mean are they considered to be human size at this point and are not subject to the rules of giants?

Yep.
EARTHBOUND This character has the (foot)speed mode instead of its printed speed mode and the (starburst)damage mode if it has the (giant)damage mode. If this character is soaring when it gains Earthbound, deal it 1damage. This power can’t be countered.

So if it shows you don't have flight or Giant status and act as a normal figure without them (can be carried, normal adjacency and LoF rules, ect.)

Tarnish

earthbound=normal non-flying figure

Not necessarily. A colossal figure only has its speed-type changed by Earthbound.

mispost......