Comment by tails4e

The RP2350 lets you choose between 2 RISC-V cores and 2 ARM cores. I believe it even supports 1 RISC-V core and 1 ARM core for those who like the idea of their microcontrollers using two different ISAs simultaneously.

Microchip Technology has a number of RISC-V options.

Depends on the task. My favorite example is a chip that has a lot more than a microcontroller onboard, but it's an old v7m. I need the rest and have to struggle with what they give. If it was RV, power PC, mips, whatever, I'd have to use it.

ESP-32C are the only mainstream ones I've encountered.

Good documentation and support.