You get extra damage (maybe 8ish), your attacks are harder to defend against (seems like harder to defend but maybe it's more), your defenses improve, and you have a chance to prevent flee.

I don't know if the hunter skills so the same.

You can counter the build up with the unpredictable edge, having a higher int than the other guy (at least for striking), blinding them(they need to see to observe), and with the fluid deceptions legacy.

Oh yeah you also get more evade along with better defenses.

In a nutshell being @fully charged@ is equivalent to having at least one offensive and defensive legacy.