OK, I'll help.
Naughty Voices is a mod developed by the same guy who made
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, and of course, OPrivacy. His mods are pretty good for a NSWF playthrough with Ostim. He hid and forbade anyone from downloading OP and NV because he's afraid of getting sued by the voice actresses after the AI drama, but of course, he can't stop us here, hope he forgives us.
OPrivacy is not a requirement for Naughty Voices, it's an entirely separate mod. What OPrivacy does is be able to ask the NPC to follow you somewhere, well, private. NPCs will say lines just before and after the act ("Let's make love" - "You were wonderful", stuff like that), and are also able to request some "private time" with the Player Character on their own. Some characters have specific lines (a married woman will say that their husband took "an arrow in the groin" lol), and Serana and Karliah get special treatment for specific approaches, as you can see their options in the MCM (OPrivacy is even able to make Karliah a follower on its own). It also has a Morning Sex feature,
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(so you can disable OPrivacy's Morning Sex and use this other mod instead for this feature).
But you ask about Naughty Voices. NV makes the characters say lines
during Ostim scenes, not before or after them like OPrivacy. "Pound me", "I'm gonna cum", you know the drill. Similar to OPrivacy, characters have specific lines according to their voices, marital status, or specifically who they are (A housecarl might say when you cum inside her: "I swear to carry your burdens, after all..."). Stuff like that.
The option you see in the NV's MCM is to choose a voice for your character if you are playing as a female (it shouldn't matter if your character is a male). The female character in the sub position is the one that gets voiced during Ostim scenes. Only one character gets voiced, so in a threesome, it will be the first female character, while the other is silent. Male voices are not supported by Naughty Voices (maybe a few of them are supported by OPrivacy, like Farkas and Viikas from the Companions, but I'm not sure).
Aside from that, not all female voices have been supported by both of the mods. FemaleCoward, FemaleShrill, FemaleOldGrumpy, FemaleOldKind, FemaleKhajit, and FemaleArgonian... expect all those characters with these voices to be silent. You will know who they are if you use OPrivacy because their privacy dialogue will be "Follow me for some privacy,
don't say anything".
Of course, custom followers that you downloaded with custom voices will be silent as well and will have a "don't say anything" privacy dialogue for them. However,
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and
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made by the mod author in partnership with another mod author called ColdSun has full OPrivacy and Naughty Voices support with hired adult voice actresses.
Both mods should work out of the box with Ostim installed (Ostim and nothing more). OPrivacy worked with Ostim Standalone with no problems whatsoever for me. I haven't tested with NV 2.7 yet, but this is the version that everyone says works with Standalone. Again, it should also work out of the box like it was back in Ostim NG.
TL;DR: blablabla, you just need Ostim and it should work