The most famous one ATM is probably “Baldur’s Gate 3” which offers a wide variety of mechanics and stats to measure if an NPC member of the player’s party is romantically interested in the player character. Two examples given in the talk I linked are the VNs “Monster Prom” or “First Bite”.
Yes and no. Like in Stardew Valley, technically you can romance every NPC in your party, but in practice you have to meet certain criteria to do so and those differ from character to character. Of course, it is possible to “game” that system.