This is very unrealistic but very interesting, also I love that you've made Tilda Swinton Queen of the UK
ITTL the Mountbatten name was created by the 2nd Duchess, Princess Caroline Windsor de Mountbatten, in the 1940s (although it was an idea even in her parents' heads since the 1930s, when she and her sibling chose to "naturalize" their paternal surname both in a simple desire to do so and to differentiate themselves from their Albany cousins.1) How was the Mountbatten name created TTL (as Albion and Germany fought on the same side during WW1)?
Oh yes, mainly through the idea being considered fringe even at the time of its proposal, because the person offered declined on its early stages or through unfortunatte happenstance. For example:2) Have there been any proposed Imperial Kingdoms that didn't happen?
Because I needed to update it, now it should appear (although the Dynasties map still needs me to do a more thorough revision so It shouldn't appear there for a bit yet)3) Why isn't Carniola featured on the map?
An ITTL Duke of Brunswick, as the House of Brunswick-Wolfenbüttel didn't become extinct in 1884 and instead continued, with said duke gaining the throne of Tuvalu when the country (originally a French colony, then a German) became independent (the Duchy of Brunswick passing to his third cousin and brother-in-law as he abdicated his right to it to become king)4) Who is the ancestor of the Tuvaluan monarchy?
Yes, in a sense, they're more like condominiums between Moravia and Silesia who are also in a manner ruled by five other branches of the House of Hapsburg (so they could be also considered small states within the two, who are also within the greater UHE)5) Does Moravia have any exclaves?
She's her aunt, actually6) Is Astrid, Nordic Empress sister of Beatrix of the Netherlands?
It isn't, Galapagos is a Crown Dependency7) How did the Galapagos became a independent country?
He died in a train accident (no-kidding, he actually died due to his train suffering a catastrophic derailment while on a visit to Belgium)8) Why was Maximilian II of Mexico's reign so short?