My 2 classic options would be
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Split the game in 2 or even 3 4-5 persons tables, works way better. On a tabletop game, if everyone takes a one minute turn to act, 10 players means you need 10 minutes per turn, it’s slow not just RPG, but in boardgames too. So split into smaller party.
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12 players, rule-light, look for a parlour larp. There is some “easy to set-up” parlour larp, with very simple mechanics, and that you can play in a 2 room appartment (or even a barn) so they’re not as big/complicated as actual larp with big rule-books, 100’s of players, and a whole castle. Just like a real LARP, it requires a bit more “buy-in/prep” from the player, but it can be a great experience. As a rule of thumb, plan 1 extra hour before game-start for briefing/set-up, and 1-2 extra hour for debrief/cool-down (turn out that after such an intense experience most player don’t want to go home immediately but talk about-it, especially if PvP tension was rising until the final scene which is a classic larp format)



Then I would recommend again the LARP route, either as a “light indoor larp for 10 people” or at a 10 people faction at a larger game. When I was active part of an online RPG community, we would join a LARP per year so we could play a large faction and see each others IRL. Often it was more the “Barbecue LARP format” so the not that great one but you end-up doing a barbecue and getting beer in a ridiculous costume