The protrusion is indeed quite similar. There are other swords with scabbard protrusions, like for example Taiwanese aboriginal knives, but those scabbards tend to be wood, not leather. The tips on Ethiopian gurades bear the closest resemblance to the tips on Berber cutlasses.
I am not sure we can settle attributions by a matter of voting
. Personally, I do not even know how to vote, as I can see the following possibilities:
1. A North African sword from areas close to the Spanish colonial holdings: North Morocco or Spanish Sahara (or Spanish Guinea?). The Spanish mottos can be explained as a result of no alternative sources of blades. We know that colonial powers tried to limit access to weapons for the local population in controlled and neighboring areas, or it may simply be a matter of restricting trade to merchants and goods from the respective Metropole. If that hypothesis is true, it may explain why we see almost exclusively Spanish blades on these swords, and mostly French blades on Mandingo sabers, in areas not too far.
2. A Caribbean weapon, which combines features from the diverse demographic composition of the Spanish colonies in Central America. By the 19th century, the population in the Spanish part of Hispaniola was of mixed Spanish, African and Amerindian descent. This may explain why the inscriptions refer to this particular island, while the decoration, which varies from simple geometric patterns to complex floral designs, is so eclectic.
3. A private purchase, non-standard issue weapon of Spanish officers and/or soldiers or sailors, who saw service in various parts of the Empire.
I am sure others may come up with further possibilities. In the end, I am afraid we will need photographic evidence to resolve the mystery conclusively, assuming of course that the use of these cutlasses does not predate photography.
Regards,
Teodor