Hi Buendia,
Welcome to the forum!!
You have certainly made a nice entrance with this excellent example, which I believe is likely of the period you note, end of the 17th and into the 18th century. From the photos everything appears correct, and with the thumb ring I would presume this is a European cavalry sword. I would need to check references to be more precise, but it seems to correspond to Prussian, or quite possibly Swedish examples.
It is not a 'walloon' , which from my understanding of this vaguely placed term typically represents cavalry swords of these periods with bilobate shellguards, and the term itself was used to note swords from the low countries on the Continent.
Look forward to more entries on this, I'm sure with better assessments.
The marking appears to be applied in interpretation of similar markings intended to suggest quality on blades, with this a singular impression of the well known 'sickle marks' used in N.Italy, Austria and Solingen. These were of course placed on the blade center laterally and in pairs, contrary to this apparantly spuriously applied version.
Above that seems to be a cross, suggesting that these markings may have been intended with amuletic value, a practice which seems to have been well established in these times.
All best regards,
Jim