Good idea, sometimes it's hard to remember all the icons when switching to a job you haven't used for a while. I'd actually go a step further: a help mode for the cross hotbar. In help mode, the action names would be displayed, but additionally, pressing an action would display its description. I think R1+touchpad is still free? It could even cycle through both proposals (show action names → help mode → hide action names). Just brainstorming …

The use case is pretty well covered by virtual mouse, but still, this would be a nice little QoL feature.