Unfortunately, there is no way to split-screen on Wreckfest.
Unfortunately, no. Wreckfest does not support split-screen play on Xbox One.
There are a few ways to play 2 player on Wreckfest. One way is to use split-screen mode, and the other way is to use LAN.
Yes, you can play Wreckfest offline by downloading the game and playing it without an online connection.
Yes, Dirt 4 does have split-screen.
Dirt 5 does not have split-screen.
Yes, Dirt Rally 2.0 does have split-screen.
Yes, you can play with 2 controllers on Wreckfest.
Yes, Wreckfest supports crossplay between Xbox One and PlayStation 4.
You will need to open the following ports in order to play Wreckfest: 80, 443, 23, and 3074.