Twist of Fate chapter eighteen coming tomorrow! <3 I also have another series that I'm workshopping! It's called Divisa (which is Latin and Italian for divided) and it's a LADS x reader where the reader isekai's into the world and the MC is still present. So either they will look the same (same name, same look, etc) or you will be you and the MC will look like your LADS MC. I'm not too sure on that part yet, but I already decided on your evol!
It's an Anhausen Class (like MC) but it's Absorption, so basically the opposite of resonance. While resonance amplifies other's power, Absorption will borrow their powers for you to use. And unlike MC, your Evol Level can be determined. So her's is unclassified since it's unstable but yours is a Level S, the highest level.
Whether MC looks like the reader or not, she will have the default hair style– the long black hair, the thin build. She will completely look like the protagonist besides her face.
My main struggle with this idea is just how will the male leads choose you over their reincarnated lover– I'm not 100% sure, but it'll either have an OT4 ending or I'll just have a separate ending for each male lead.