I’ve got a 2010 outback and my GF has a 2015 (I believe) the 2 annoying things are the seats don’t fold flat, so the game gets hung up on the bump from the seats. Push HARD and you can get them in.

EMs fit just fine, and 6803’s fit perfectly with the head of, almost exactly 1/4” clearance between the game and hatch opening. Really tight.
Data East Torpedo Alley was wrapped in cardboard so that probably did me in. Would not fit, had to hang out the back and drove 3 hours home like that. Not a huge issue.

Stern Electronics games fit just fine as well.

Gonna find out if I can remove the stupid plastic molding from the back because it’s useless and takes away about 1” of clearance that you desperately need

As an update, I moved a Data East Checkpoint (‘91) in my 2010 Subaru Outback. Game gets stuck about 2 or 3 inches before the rear hatch can close.
The roof unfortunately has a plastic piece that bends downwards. I really wanna just rip it out lol.
A 6803 without the head just BARELY fit.
I’ve just accepted that I have to strap the hatch down and always have several ratchets on hand.

Just to make sure you check the weather or bring some tarps!