Other applications ...

Some ATMs have unmarked physical buttons next the screen and tge text displayed on the screen next to those buttons defines what the key does.

TV remotes have A/B/C/D (red/blue/green/yellow) physical buttons whose function is dynamically defined by your context or which setting / function / menu you are currently inside.

I guess this goes back to video game controllers that have A/B X/Y buttons that can have different Functions in different contexts.