Well, apparently the Mourish Occupation of the Iberian Peninsula was what brought to the Dark Ages Europe advanced irrigation techniques which spread from there increasing agricultural production, the growth of cities and ultimatelly the Renaissance, so we probably would need to pay them, or at least their descendants (mainly Northern African Arabs).
That said Portugal at least in this is a joke (and I say this as a Portuguese National) - for example some years ago the local politicians came up with a scheme to give the descendants of Jewish Sephardites (a group which was expelled from Portugal in the 15th century) portuguese nationality, which is quite an “interesting” choice of “reparations” taking in account the country’s much more recent and way more harmful history of Slavery.
Anyways, the whole thing is corrupt as fuck, with for example Jewish Organisations in Russia providing wealthy Jewish locals with “proof” of their Sephardite ancestry for the purpose of gaining Portuguese Nationality (which is only worth it because it means EU citizenship), to the point that the present day richest and most well known portuguese national is Roman Abramovich.
This talk now is in the sequence of that crap (which continues, which for example some Hamas hostages given expedited Portuguese Nationality to try and secure their release as “portuguese”), the sudden rise in the recent elections of the far-right party who are the only nationalists around (so the only who frown upon the whole giving away of citizienship to people who never ever even visited the country) and the Portuguese President (who is basically a powerless figure who loves media attention) having suggested that Portugal and Spain should “compensate” former colonies.