A crossover is a vehicle built on a car platform but larger and with higher clearance. Something can be both a crossover and a liftback.

Of course, neither it nor liftback are legal terms.

Both are larger (indeed, both have 7-seat configs, something few EVs can boast, and MX is one of the largest passenger EVs out there, and both are higher than their car configs, with MX clearance of 5,7-8,1" (adjustable), vs. 4,6-6,2" in the S.

The IRS and NHTSA actually classify the Y and X as SUVs.