Spy stuff is not going to work for non spys. Rendermode or color is a better bet.
You can set weapons, wearables, and clients to be transparent, however you can not remove tempents or client side effects.. So unusual hat particles, or arrows stuck in the player will still show. I dont know how to go about removing arrows, for hats and such, you can just kill them if you really need to.
When hiding weapons, make sure that you hide disguise weapons on spies
For transparency you can do 255 255 255 0 if you are rendering alpha, try rendermode_color