I don't know if this has been here before, but looks interesting.
https://www.microchip.com/wwwproducts/en/ATSAMD51N19A
The SAM D51 high performance micro-controller series is targeted for general purpose applications using the 32-bit ARM® Cortex®-M4 processor with Floating Point Unit (FPU), running up to 120 MHz ,up to 1 MB Dual Panel Flash with ECC, and up to 256 KB of SRAM with ECC .
Adafruit is developing boards for these.
https://www.adafruit.com/product/3382