I know that EPYC and Threadripper CPUs are the best for CPU mining and I am able to have a threadripper CPU with 16cores, can I use this to mine some Ethereum in this bear market or it's not worth it? I have free electricity but my aim is mining difficulty.
Check your profit in the Raptoreum calculator. If you are satisfied with such a profit, then continue mining. You can sell the processor and buy a video card, but in the last month the profit in GPU mining has also dropped a lot.
https://mineraptoreum.com/