Nagant M1895 and Webley-Fosbery Auto Revolver tagged. Also made a tag for the Schonberger-Laumann 1894 that Princess is holding. I knew I saw it before so I dug up the Forgotten Weapons video of it.
EDIT: Beatrice might be holding a Webley Bull Dog pocket revolver, befitting her status in the group and the fact we seem to have a theme of Euro-only guns here.