Are they both blue tortoiseshell? Michelle def looks like it.
Mmm ... Not sure...
The photo of Michelle is a bit deceptive - She doesn't actually have blue patches, it's just the blue showing through under the blonde.
Isabella = Beige = Blue Sootyfawn = Blue Torteshell
They're all different names for the same colour!! Beige is the official name though.
Michelle is not the same colour as Lexie, she looks like a Fawn or a Fawn/Blue Harlequin, would need some better pics to tell as you say the one with patches is deceptive.
No such thing as a lilac fawn - you can get a lilac sootyfawn but again its just another name for Isaballa.