1 - You don't need her ECA or IETLS if your CRS is 456.
2 - You cannot apply as single, that would be misrepresentation. You can apply as common law with non-accompanying dependent, she can then apply based on her own merits via EE or you can sponsor her.
I have 1 question regarding the common law in my application I submitted. Me and my girlfriend have a kid together though she lived in Sweden and me in Canada and I have applied her as a common law in my Express entry and we had lived like a month together but Cic now asking me to prove my relationship that we lived 1 year together. It's hard to prove I already submitted the details when I initially applied. ( Though I didn't claim any points of her). Is there anyway where they can just issues me P.r. cuz I was misrepresented by a consultant can I rectify the mistake.