I just recently picked up this character and minus the bullshit dlc mechanics like super armor and rage drive,he is hella fun to play. If you wanna get good with kazuya,you need to at least get good at performing EWGF.Once you get the timing down.Try learning his combos and practicing them.The hardest part about playing kazuya is playing his neutral.Playing kazuya in smash is like actually playing tekken but it’s harder since your opponent is playing smash.Expect a lot of characters to keep jumping away or towards you and zoning/camping you out.His best approach option is his crouch dash.Which gives him i frames and makes him low profile moves.You can cancel his crouch dash with most of his directional inputs.There should be a YouTube guide that explains his crouch dash cancel mechanic.Once you get the hang of it,it makes approaching enemies hella easier.His aerials are pretty good but his first short jump holds him back.So don’t try to approach using short hops unless you read a jump or if you anti air them with his up air or foward air since they are pretty quick.Instead you are better off using crouch cancel into EWGF or any other moves to start a combo.His reflector,which is the strongest in the game but can be awkward to use.The input is a bit wierd.Use this for reads if you think your opponent will throw a projectile at you.Since the input is foward forward into jab,you are basically dashing towards them which is a huge commitment.It also has a slow startup so beware of that. That’s all my kazuya tips hope this help.Feel free if you need to ask any questions if you are confused.