The stator design can vary depending on what the motor is intended for, meaning 1/10 2wd or 1/8 4wd off road for example. The basic setup is 2 or 4-pole rotor with 6 slots around the can. Basically each phase has 2 windings but, in the case of airplane motors the stator is divided up into smaller sections in multiples of 3. Say 18 total or 6 windings per phase. They can also be "slotless" as well. There are many ways they can be built.
Depending on the design of the motor and the ESC you run it from there might be some compatibility issues. The ESC will still create the rotating flux field electronically but the motor may cog if the number of sections / poles doesn't sync up well with the ESCs rotation as it's running. You'll find forums of guys asking about why their Castle motor doesn't run as fast as their stock Traxxas motor with the same ESC even though the KV rating was higher. It turned the motor but there were some timing issues and in the end the motor ran slower. The Traxxas motor may be slotless also because when you roll that motor by hand the rotor doesn't jump between the slots of the stator. It's a fluid motion so I'm assuming it's slotless. Someone can verify this independently. If you get a system then of course it's designed to work together. For the most part you probably won't have issues when intermixing brands but it can happen.
You might be able to find some chart or other reference for the sizes. I don't know off hand.