Concerning the blade etch I have to add that there were firms that obviously had a preference for the one or the other etch. EG PUMA navies mostly (always?) are known for sailing ship etches. I think to remember that PACK had either an own special etching or the sailing ship etching. EICKHORN only (mostly???) did use the fouled anchor. WKC did use both motives but mostly combined with special other features as yellow gripped with hammered scabbards mostly (not always) had the sailing ship motive, those with white grip and lightning scabbard had the fouled anchor.
The current availability of a firm, a makermark, also might have had influence what dagger (therefore what etching) was chosen to be bought by the officer.
You see, the answer might be very complex.

Concerning the mark in the hanger buckle I have to add that those marks are rarely encountered. Another "mark" I am well aware on those buckles is the "tree points" mark. On rare occasions the buckle are marked with the navy acceptance mark.

Regards,

wotan, gd.c-b#105

"Never look for sqare eggs" as a late owner of an original FHH-dagger used to say.