yes a lot of questions not only by you
a few things we know ;
I have four statements that may be considered personal assumption.
these type of hanger is used by sailors and troops and were no gifts or processional weapons !
see picture from Blanke wapens /Puype, a sailor of the regiment Fourgeaud 1772-79 in Suriname wearing a hanger of this type. btw I'm ashamed of the dutch colonial past.
JP puype held a lecture in the 70ties on the topic "From boating and fight -. Tactics and weapons in the sea battle during the third quarter of the 17th century. "
The bladed weapons are of interest to our argument, since around the middle of the 17th century, first types were developed and intended specifically for the sea service. Those were enteric cutters, which in large quantities were ordered by the admiralties. A "houwer" was a sword with a short, relatively heavy blade designed to cut and less for stabbing. Often the hand guard was bulky and could e.g. consist of a large, convex plate.
this type of seaservice hanger is a development of the dussage and has been used over a long period of time. 1600-1800
the blades were imported from Solingen and other production cities and assembled in the Netherlands.
loose blades were carried as cargo on the ships and were used in the colonies as spare parts, where they occasionally were given a local hilt.