Never done this before, but have always done an October horror movie challenge over on the DVDTalk forums since 2005.

6 countries
USA - Old
Italy - Cruel Jaws
Uruguay/Argentina - The Last Matinee
Canada - Resurrection
France - Devil Story
South Korea - Gonjiam: Haunted Asylum

8 decades
2020s - Freaky
2010s - The Babysitter
2000s - Eight Legged Freaks
1990s - Resurrection
1980s - Eyes of a Stranger
1970s - The Fifth Cord
1960s - The Curse of the Werewolf
1950s - The Giant Claw

2 folk horror
Jug Face
Pyewacket

4 films from 1981
Eyes of a Stranger
The Boogens
Hospital Massacre
Blades

2 films from your birth year (1988)
Primal Rage
Deep Space

2 haunted house films
The Nesting
The Others

The worst Part 2 that you haven't seen
Piranha II

1 film set in the woods
Eden Lake

1 Kaiju or Kong film
The Giant Claw

2 Hammer films
The Curse of the Werewolf
Demons of the Mind

3 films with a person of color as director or lead
Candyman (2021)
Ma
The Hearse

3 Asian horror films.
Pulse
Wolf Guy
Gonjiam: Haunted Asylum

1 Tobe Hooper Film
Mortuary