theory | how QUEER is the MIMIC...
the most important question of all. is he gay and trains
To truly find out about Mimic's queerness, we have to look back into 197X-1979, when it was first built. It's likely that M1, the first and successful iteration of Mimic, was intended to be a gender-neutral companion to David. See how Edwin introduced it to him!
"David, I want to introduce you to someone. This is M1."
"Owh- It's an endoskeleton, it won't always look like this. It'll wear fun costumes!"
"Anything you want. It can fit into any costume we've created. Think of it as your new babysitter. But, it... doesn't get paid and go home. It'll stay with us and help around the house."
Mimic is explicitly referred to with it/its pronouns and as a babysitter. M1 probably wasn't Edwin's false wife to begin with, she was turned into that when Edwin was coping with loss. He made something that he could utilize and took the opportunity. There is a chance M1 was intended to imitate Fiona from the start and Edwin wasn't ready to admit it yet, but both options seem just as valid.
M2 on the other hand is a separate program branched off of M1, retaining the memories and code and just building off of it. M2 is primarily masculine in presentation, using he/him pronouns in addition to the default it/its.
Both F10-N4 and M2 split off of M1, with F10 continuing the Fiona imitation and M2 becoming his own thing, intended to become David but opposing it. (pursues data diver to break it, likely maims own components to make sure it cannot be "fixed")
But, M2 isn't in any way explicitly "male". It frequently disguises himself as female characters and even had built-in high heels in the legs it gave itself. If anything, The Mimic is genderfluid, or at least gender non-conforming. Gender doesn't seem too tied to identity, though, more so as another layer of disguise to put on. Just like any other aspect of a person, Mimic imitates gender.
As for sexual or romantic orientation, there is a simple answer: no. Mimic isn't that kind of bot, while it is a complex character once you peel back the layers, it does seem to operate best on fewer emotions. It could possibly replicate loving acts of service if it can get something out of it, but it likely won't bond with anyone unfamiliar to it. He did 'grow up' with only two close people, if you count the comically busy Edwin.
Mimic seems to prioritize function and survival over the little fun things, and romantic commitments would only distract it from his greater goal.
Mimic is likely aromantic-asexual. Won't fall in love unless it's beneficial (it's not), and doesn't have the biological drive to reproduce. He is friend :]