Now to step back into reality...
While on the surface it may seem to be a simple question, in fact it's much more complex question that many may think unless they've done a lot of custom scratch builds before. There is a ton of info available on the internet about what users have used for any specific make/model of a RC craft as well as the info ( if they provide it ) from the manufacturers may recommend. The trouble is that the info isn't available from any one location or place... That is a pretty large question when you are talking about a known make/model... add to this that now we are talking about a model that hasn't been made or completely spec'd out and now coming up with an answer becomes close to impossible.
This is what I did when I was looking for the impossible when it came to scratch building an airplane ( which there is much more info on than there is on multi-rotor craft ).... I take the information that I know or have a close estimate of.... then I look for existing models that match ( as close as possible ) the same set of specs that I'm looking for. Now that info gives me something to base a search on and then I can see what others have done for their craft and how well they feel it works.
When looking for actual motor data... you probably won't find it ( or much or it at least ) listed with the cheap motors found on sites such as HobbyKing, Gearbest, Banggood or similar sites... More often than not, those companies can care less about providing any real information, nor do the manufacturers of the products they carry. If you want real info on motors, look at the websites for known quality manufacturers first... When you find motor specs that you think will work, if you wish, you can now use that info to find the cheaper motors from these other places, just don't expect the quality or performance of a top end product in the bottom end products that many of these places carry.
It' s not going to be an easy search in many cases.... but often the end result and the experience you end up getting do pay off in other ways. I didn't do a lot of this myself ( just a foamy or two ), but my Dad did nothing but this during the last years that he was able to enjoy the hobby ... even today he still creates some of his own foamy planes to play with but at 84 years old, he doesn't do much of it.