Is this only for the literal action or can it be used figuratively as well? (such as someone who's in line for the throne.)

Hi Mme,

No you cannot use 'Faire la queue' figuratively for 'in line for the throne'.

In French you would say :

"L'héritier (heir) dans l'ordre de succession au trône britannique est Charles,le prince de Galles. L'héritier apparent est William, le duc de Cambridge, et l'héritier en ligne est le Prince George, son fils."

Hope this helps!