Two lights on a 3-Way Circuit with Separate Dimmers
Q1: With your existing setup, the short answer is:
No, you can't do that without separating the circuit.

Q2: You could add a dimmer at the each location that would dim each light separately but you would have to run at least one more cable depending on your current wiring diagram. Then the three way switches would just turn the lights on and off and the dimmers would dim each light. It would be complicated and a pain to install. Sounds like a lot of work to me for the result.

With a 3-way circuit the lights are all in series with the switches. Effectively, all on one wire at any moment. Whatever dimming you do at one location affects both lights.

Good luck and stay safe!