Yes, but the "worldwide" M3 at this point are coming from China. Since CATL is making the LFP batteries in China, I'm sure the bottom line price of using a China battery in a China car is less than a China battery imported for installation in a US car. I'm a former "Big 3" engineer and I promise you Tesla is going to pick whatever battery will allow them to make the most cars at the lowest cost. Cost is always the answer.
LFP comes to US if battery production in Nevada becomes supply constrained OR its way cheaper and you don't mind running Nevada at less capacity. I think the later is unlikely since the Nevada plant is a JV of Tesla with Panasonic and they have a more vested interest at a high utilization rate.