Epigenetics

Can somebody explain how epigenetics works in relation to using donor eggs? I understand the concept of it but am still uncertain about what traits it actually influences.

I've had people tell me their donor egg baby looks like them or has their personality. But is this the work of epigenetics or because the intended parents chose a donor who may have looked similar or had a similar personality already?

Does epigenetics enable the mothers body to pick and chose which donor traits gets passed along to the baby?