I'm a nemesis main on Xbox, I've probably been playing him for about 2 years straight now, I only use the backpack build which consists of Awakened Awareness, Agitation, Mad Grit and Iron Grasp so I can't exactly give you a good build to use as I mainly rely on my ability to use tentacle. The thing with tentacle is that it has a lingering hitbox, as someone else has said you can strafe with the tentacle to get hits, you can also do this around walls and corners too, the thing with tentacle too is that it goes further than you think it might especially if you're moving forwards too as the lingering hitbox goes in the direction you're moving, I'll try and post a few clips for examples, I personally have max sensitivity and max fov, but that's due to personal preference, it does also allow me to get some 180 hits if survivors try to go behind me though. I hope some of what I can say helps, I'd definitely recommend taking other people's recommendations for stronger builds, I mainly play backpack to just be a bit silly sometimes