Space marines don't really fuck because they're indoctrinated from a young age into it and probably don't get to experience a true sexual awakening unless they're already implanted with the organs at an older age. Some of the more zealous or bloodthirsty chapters probably forgot what sex was.
Probably not unheard of in chaos space marines but some emperor's children interactions certainly implies it
Tau have a government mandate on when and how much they can fuck but it doesn't applies to other races in their empire
Deldar I don't need to say it of course they fuck
Im unsure about craftworld eldar but im inclined to say no because they are too focused on the path system and not falling for Slaneesh again
Harlequins would fuck if their role demanded it
Orkz don't know what human sex is about and only reproduce through spores
Tyranids only build themselves via biomass and the hivemind and don't reproduce sexually. Im unsure about if the genestealer's kiss is sexually acquired but anyonr with it breeds and breeds hapla bug children extremely often.
Admech use birthing vats and early indoctrination it's likely their doctrine hates sex
SoB don't have to take a vow of celibacy but nost of them don't have sex freely
LoV use only birthing vats and it's likely they don't even have dicks because their forms are perfected exclusivly for mining and making profits
Custodes just go back to SM
Inquisitors FUCK, Rogue Traders FUCK and ship captains FUCK
Guardsman can't resist but go on turbo sex mode the moment they get on a mixed regiment but during their duty they probably don't fuck often