Since the 3700X and 3800X 8-core CPUs are already available, the launch of the 3750X for retail channels might not happen at all. The specs would have to be too similar to the 3800X and a price point between US$330 and US$400 would not really be that justified. AMD may consider launching the 3750X model for OEMs, however.
https://www.notebookcheck.net/AMD-accidentally-leaks-the-Ryzen-7-3750X-CPU.439755.0.html