Alright. First off, Hui is a melee fighter. The entire premise of TGoHS is that everyone is participating in a Martial Arts Tournement. On his page there should be a list of all the moves he knows with descriptions.
This brings us to his Air Manipulation. It's not true Air Manipulation per se, it's just Hui using his Martial Arts to use air based projectiles. As a reference, the original Jin, was able to copy
Han Dae-Wi's Blue Dragon Storm, which is a concussive blast of air. Though, Hui can't use this move. Hui on the other hand, can use other attacks, which are listed on his page.
Now for his weapon. Since his character was based off
Sun Wukong, his weapon is an extendable staff. this staff can extend, increase in size, and after training with a homeless man, curve as it is extending. This staff may say planetary on his page, but it only has shown Planetary feats when in Monkey King form. Now I'm not saying he can't do it when he is in Base form, but he has almost never been shown to expand it at levels that he can do in his Monkey King form. I'm assuming he is perfectly capable of extending it, but he just lacks the strength in Base to carry it.
His staff also only broke after a 5-A shattered it, so although not as powerful as the original, it's not going to be broken by Holo-Pearl anytime soon.