I'm looking for a fic where Buffy travel through dimensions, in one there is the Smashed Spuffy sex scene with Faith in the mix, in another she was in a relationship with vamp(?) Cordelia.
Thanks tó everybody who could help me.

Hi,
It's sleight of hand and twist of fate by bisexualbuffy on EF aka derekmaliknurse on AO3.

Summary: It's just Buffy's luck, really, that as soon as she reunites with Spike, they get thrown into a series of alternate universes with the Scoobies along for the ride. 

https://dark-solace.org/elysian/viewstory.php?sid=6579
https://archiveofourown.org/works/26151451