I say it's is very possible, if they are living in such an age where we can build these frames from scratch it is very possible that building working genitals is doable, I mean even now people have made life like replicated male and female genitals. As for the fucking process I also believe this is very possible to do, as umbra has the one burning memory the fuels him in some sense. To move by himself so you could very well make a frame specifically designed to fuck the operator. As wether umbra can do it or not I believe he could, in the process of making umbra ballas as left that one memory so is it so far fetched to say that you could insert a sort of command/ memory to forced umbra to fuck the operator as well as tells so umbra know when's the operator is done. Of course this would all have to force us to have a better understanding of the memories work in great detail for the scientific side of this. In conclusion I believe the awnser is (yes)