Nah for real, I think it would be kind of interesting to see more of the daughter's thought process and their pov of wtf is going on and how they see it all. I think so far we only got 1 singular thought bubble (correct me if I'm wrong) which was when one of them wondered how Andrew had all those female mannerisms down so naturally. Do the daughters really expect the (former) husband of their cousin to replace their mom?
Completely agree: I can't really figure out/decide what I think Nikos and the daughter's perspective on any of this. If we take these to be the facts:
1) The family is aware of a spy camera and that they're under surveillance.
2) Andrew has asked the family to treat him like Elena.
With the speculated aspect:
a) Andrew/Marina have presumably spelled out that Andrew is acting as Elena just because they feel keeping up those appearances is in the family's best interest in terms of safety.
Then...
Nikos remains in my mind, a really fucked up guy. Either he's that lonely, that horny, or has such a strong fetish for feminized men that he's taken every chance possible to "reduce" Andrew to an Elena caricature. The multiple proposals, the kissing, the sex... No matter what Andrew had claimed, especially given the circumstances where he's essentially only staying as Elena under duress, it's not romantic behavior. It's manipulative and self-serving. And to do so multiple times in front of Marina is extra fucked up. I just don't see an "innocent" interpretation of this. But I can see how a person could be like this. There's possible motivations that lead to this behavior.
The daughters on the other hand is weird. Possibility 1 is that they just really love their father and want him happy. So they're happy to help feminize their cousin's husband to reach that goal. That's possible I suppose, but going that far for even your father feels like a stretch. It'd be one thing if they were doing this to a stranger with no connection to their family, but I can't fathom doing this if they had any positive relationship at all with Marina. That's just needlessly cruel to Marina, if they are "normal" people.
Possibility 2 is that the daughters, particularly Sofia, are way more in to feminization than their father. If Sofia really does get a kick out of this, it may be that no matter her feelings toward Marina, the fact that she's helped turn her cousin's husband into a sextoy for her father might actually be a plus. After all, sometimes, the more taboo the better. It's possible they're looking for a "plaything" just differently than their father. Like, Nikos uses Elena for sex. But the daughter's aren't using Elena as a mother figure, but rather a dressup doll. A toy/accessory for them to play with for various occasions and activities.
If neither of those are in play... Then you have two young women, that know that their cousin's husband is pretending to be their mother to keep them all safe. If they don't have "nefarious" reasons, the only other interpretation I could see is that maybe Sofia finds it funny. Let's assume she doesn't know Nikos has been fucking Elena at night. Maybe, she sees the dark humor of Andrew getting stuck in this situation, so she prods because she finds this whole situation more amusing than scary. So stuff like the engagement ring, and her teasing, is because she doesn't want/care about making this permanent, but it's so amusing to her she just wants to push it as far as it can go. This would make particular sense if she thinks Andrew is overreacting, and doesn't find the threat that credible, but finds it funny Andrew and Marina are "overreacting".
I suppose, you could say she could find it funny that Andrew is getting fucked by Nikos, but to me, that feels harder to justify. Like, it's one thing if I only thought my father was kissing and flirting with my cousin's husband to keep up appearances and it all making my cousin and her husband uncomfortable. I think that it's another thing to find out that your father has decided to fuck your cousin's husband. Maybe that's splitting hairs...
Regardless, if the daughters are "innocent", I can't see them wanting this to be a permanent thing. They're already fully grown women and Andrew can be argued as not being a particularly interesting person. Like, if their father was pursuing a famous makeup artist (since that would relate to their business), or someone rich, or even an actually famous actor/actress, at least having that person around would make for some interesting stories. But they know this person as their cousin's husband. Why would you want to separate them? If they had known Andrew before, and thought that Marina was a terrible person, and they were "rescuing" Andrew from Marina, I could see an "innocent" angle. But there's nothing supporting that. So again, why are they so apathetic at best or cruel at worst to Marina's feelings?