Crossbow's good enough, provided you're using it on single zombies and not a crowd other wise you're going to need some kind of tricked out Joerg Spave Repeating action "Let me show you it's features!" kind of deal. You could make something like that, but it would take a lot of engineering.
https://www.amazon.com/Ace-Martial-Arts-Supply-Tactical/dp/B079Y8L198
Something like that could work too, though it's very short range (I think the tests I saw were about 15 yards) it's got just enough punch to work at close range.
Tennis Racket: You could use it to knock them down I guess? Maybe serve grenades into mobs? That'd be awesome if you could pull it off but you'd have to be a hell of a Tennis player with light as heck explosives. A Lacrosse stick would probably work better for that sort of shenanigans. Better than your hands but not by much, nearly anything would be better.
Pool thing? If that's supposed to be a man catcher it could be handy in a group, Loop a zed, hold him in position while another member of your team brains him, definitely not a solo weapon, very situational.
It’s just an amazon.com Cobra Crossbow with a “magazine” on top and a modified stock. The guy didn’t invent the cocking function.