Curt Manufacturing has a trailer hitch, custom fitted for 2018 Outlander PHEV.
https://www.curtmfg.com/part/13398
I just ordered mine from carid.com
https://www.carid.com/2018-mitsubishi-outlander-trailer-hitches/curt-class-3-rear-trailer-hitches-893893067.html
Should take 30min - 1 hr. Good...