Re Ships:-
I have several URLs - this one appears to be fruitful:
"Books, boxes and Boats", which includes an option CLIP Vessel Data by Ship Name
If you search for ships starting with "Prinze" (to allow for misspellings), that brings up just one ship - Prinzessin. Selecting that gives us important information like the Official Number 143077, and basic details. The last line of details refers to the ML (Merchant Navy List) of 1920 which shows 143077 Prinzessin to have been registered at London 1919 and built at Hamburg in 1905. It appears to belong to the Union Castle line of London (column headings are visible on the previous page - page number is near to the top right). Nett tonnage 3697, gross 6387, engine horsepower 622.
Near the top left is Year - if you click on the down arrow, you see the 1919 entries for the MNL, with no Prinzessin. This suggests one possibility to be explored - that Prinzessin was handed over to the Allies at the end of WW1 as reparations.
Quite often, it then makes sense to search details of the shipping line - Union Castle's ships are accessible (sort of) from Union Castle Mail Steamship Co Register and the WW1 Managed Ships section has an entry for the Prinzessin. This entry includes a photo and the data that the ship was managed from 1921 as the French ship General Voyron. Learning point: things like the Merchant Navy List are British documents and while removal from the register may mean it's sunk or dismantled, it may also mean that it's been sold out of British service - where British probably includes British Empire.
The General Voyron name is more amenable to searching and turns up this Wikimedia link:
Category:Prinzessin (ship, 1906)
That confirms Prinzessin was seized as war reparations and indicates that she was built as Prinzessin for the Deutsche Ost-Afrika Linie, Hamburg. Whether there is much more data available, I don't know - searching for Prinzessin gives way too many answers as the word simply means Princess and even restricting it to ships doesn't help because the earlier Prinzessin Victoria Luise is regarded as the first cruise liner so has a lot of internet entries.