Inside the Station M2 there’s a Rockchip RK3566 SoC, at the heart of which is a quad-core Cortex-A55 64-bit processor running at up to 1.8GHz. This is the successor to the A53 chip used in the Raspberry Pi 3B+, Nintendo Switch
While there are four A53 cores physically present in the Nintendo Switch, they are unused. For some reason it only uses the four A57 cores on its Tegra X1 SoC, with one reserved for the OS. I would think it would make sense to use all four A57 cores for games and use the A53 cores for the OS, but Nintendo.