Magnetic usb c adapters: adds universally compatible magsafe+data transfer to all devices for $10-20. Very convenient.
Kdeconnect, scrcpy (software): notifications, reply to messages, automute on calls... what MS and apple copied.
Keyboard with QMK or kmonad(software) or other software: e.g. caps works as both ctrl and caps. Easier umlauts. Multimedia keys, shortcuts etc on compact keyboards.
Screenbar: convenient lighting.
Droidcam, camo (software) or hdmi capture cards: again sherlocked, but the original software gives you much more control.
Wacom tablet or sidecar-like: since apple and samsung sherlocked the idea, the original apps dried out a bit. Use a tablet as a wacom contiq. Preferably wired.
Audio interface: use professional mic, headphones with your pc. Also eguitar.