Taken from
My fave tropes from most to least favored
1 A/B/O
2 Hurt/Comfort
3 Sex Pollen
4 Royalty/Arranged Marriage
5 Soulmate Identifying Marks: Tattoo, Red Thread of Fate, etc
6 Loyalty Kink
7 Magical Connection (telepathy, etc)
8 Vampires/Werewolves AU
9 Enemies to Friends to Lovers
10 Rivalmancy
11 Adopting/Raising a Baby
11 Found Families
11 Age Difference (possibly due to time travel)
14 Fake Dating/Fake Marriage Accidentally Turns Into Feelings
15 Coffee House AU/Food Service AU
16 High School/Uni AU
17 Seemingly Unrequited Pining
17 Fake Out Make Out
19 Role Reversal AU
20 Amnesia
21 Friends to Lovers
22 Espionage AU
22 Incest
24 'Groundhog Day'/Karmic Time Warp
24 Reincarnation/'25 Lives' AU
24 Trapped in an Elevator/Snowed-In Cabin/etc
24 Selfcest (possibly due to time travel)
28 Actually Unrequited Pining