Hi Ian, your Sudanese arm dagger script on the blade may have the twin cities of Omdurman or Khartoum engraved on the blade. This is the most common engravings that I see on these and are at times illegible, mimicking similar blades by more literate smiths. Other markings are using dates, typically 1898 to 1901 during the establishment of the condominium of the Anglo- Egyptian Sudan. Less often are makers or owner names but they do occasionally show up. The pommel caps are usually silver alloy but sometimes have an Ottoman Egyptian qirsh coin on the end.
This arm dagger being fitted with the silver mounts is on the above average side carved from an African black wood. Unfortunately, missing is sheath. Date is likely around 1900 – 1925. It is a good example of the type. I attached an example that I have and a link to more information about it. As for the Shona dagger, others may be able to help as I have never handled one yet. It does look to have considerable age and nice wirework though!
https://www.the-mansfield-collection...ver-arm-dagger
Geoffrey