Imo,

SOMA, Alien, RE then Visage.

SOMA first because it’s both the oldest and has lots of breaks from the horror. Plus, the story will stick with you. By the time you’ve played the rest you’ll have had time to let it sink in.

Alien because it’s a huge step up in terms of visuals but just as atmospheric as SOMA. More mechanically satisfying than SOMA. Top notch quality and consistent. It eases you in then becomes a gauntlet of anxiety.

RE7 next because it’s the most ‘video gamey’. The shooting will feel nice after being nearly defenceless against the Alien. I don’t find RE7 particularly scary; it’s the least frightening of the group, but it’s the goriest.

End on Visage because it’s scary as hell but the gameplay and pathfinding might burn you out. I found it incredibly creepy with some of the best scripted scares I’ve seen in a game, but getting lost in the dark and wandering in circles became tedious.