Disneyland Paris has selfie spots for characters. The character is behind a rope, and you keep (at least) your 6ft distance, you can interact, only no hugs or autographs. It's not perfect, but it gives some unique opportunities and costumes we wouldn't have before Covid.
For characters we have 2 variations. Both I can see working on a cruise ship. The biggest problem with the cruise ship is the 'narrow' hallways where characters meet. They will have to create one way lanes to make sure guest flow keeps going.
Examples from my last trips.
1. Characters around the park
Minnie in Frontierland
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Donald & Daisy on Main Street.
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2. Characters in a theater. As there are no shows, we have several empty theaters, these are used to have a backdrop or a full set.
You enter the theater via one side, go on stage to take your pictures and have your moment, and then exit via the other side.
Halloween 2020 - just backdrops for villains. They have a 15 second show where the villains walked on, do 2 dance steps and play Hallloween music during the sets.
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Mickey and the Magician show-theater
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The Frozen show is dark, but they use the sets to meet Kristoff & Sven and Anna & Elsa. As you can see, also the characters social distance.
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