Primarily speaking about the Gladiator ascendancy passive Outmatch and Outlast.
The '25% chance to gain an Endurance Charge on kill with Off Hand' doesn't work properly while you're Unencumbered(unarmed with Hollow Palm Technique keystone.)
Main Hand mods seem to work just fine.
External link →These should apply when you deal off-hand hits. Note that the animations will not necesasrily accurately reflect whether a hit is main or off hand while unarmed (because in the default unarmed state all attacks are main-hand, but the animations look much better using both), but if you attack multiple times in succession without doing anything else between, then you should alternate between attacks that are (mechanically) with the main, then off hand. I will investigate when I have time.
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