Keep in mind the Vision was taken by surprise when She Hulk ripped him in too,he though she was a friend. But when facing Diana,he's reay 4 battle.
"As soon as she tries to touch him he goes intangable, or partially phase into her body rendering her either unconcious or in great pain. How can she even touch him?"How can he even touch her when she's faster than he can calculate? Also phasing into her wouldn't knock her unconscious because it didn't do it to Iron Man or Storm.
The original vision could change his density from his maximum level (90 tonnes and diamond hard) to intangibility in less than 1/100th of a second.
However WW can react and move at speeds exceeding this speed of density change and with her massive strength she should be able to knock the Vision's head in 1 hit.
Also, with her reaction speed, his fastest attacks would seem to be in slow motion to her so she should be able to dodge him as he has at best enhanced human reaction speed as synthazoid.