It is normal now to have Spanish trucks with South American drivers, some Portuguese firms will use Brazillian/Angolian or from Mozambique, all their former colonies, and no language barriers.
Patinter who used to have about 3000 trucks, used Ukrainian drivers.
A portuguese truck with a spanish trailer backed into my truck in irun, the driver was moldavian. from what a coworker that lives in spain told me, they earn about €600 a month.
In the 80s and 90s, if you saw the nation of the truck the driver would match up with the same nation, now it could be anyone driving in it.
For some reason local media assume the driver of a Spanish truck will be a Spaniard just because the truck has Spanish number plates, the general public have no idea how the real world is to get the cheap stuff to them they ordered on the internet.
Years ago all the ferries would be full of Irish and UK drivers, now maybe one or two on each crossing.