Head to head
Which one will break you first?
Two fingerprints on one grid. Both are scored through your profile, so this answers the question for you rather than for the average player.
Age of Empires II: Definitive Edition is the harder of the two for you, by 1.2 points. The gap is widest on grind, where Age of Empires II: Definitive Edition asks considerably more than DOOM Eternal. If you want the gentler run, start with DOOM Eternal.
Axis by axis, biggest gap first
DOOM ETERNAL
The demons are a resource puzzle solved at a hundred and twenty beats per minute; stop moving to think and you are already dead.
Real resistance. Expect to work for it.
AGE OF EMPIRES II: DEFINITIVE EDITION
Build orders are the curve, and the campaigns teach almost none of what the game actually asks for. The hard AI does not forget its economy while it fights.
Sustained pressure. Progress is earned.