RubberPeen
Having been trained to use axes according to the english methodology I can only say that it's usually just as complicated and intricate as swordfighting up to and including finesse at parrying and weapon entrapment. Then again I wouldn't know much for one that's quite that big assuming 6 feet is the blade length not the handle length. long handle would be a polearm and require a special spearmanship or poleaxe technique whereas an extremely large blade the axe itself will move you almost more than you moving it and would need a speciaal technique of it's own unless you had super strength or tk like our mc.
If you do another world merge you should fuse his world with low-power martial arts worlds like Baki, Kengan, and Kenichi. Maybe Ranma once the MC gets strong enough to destroy a mountain. I suggest this because his power would become pretty useless in his home world if the only people who could POSSIBLY challenge him are the other two telekinetics. This way he would have at least a little excitement outside of missions.