Two coordinated Halloween costumes without identical outfits

Actual tested output. The notes used for this result are an example, not a real event. This box is not copied. Replace the notes above with your own before you paste the prompt.

Pair 1. Motif: frost on leaves (silver against green).
Shared story: an indoor night garden is open for one evening. Person A maps which plants are named after stars. Person B keeps the beds and the seed notes. They compare lists. They do not wear matching outfits.
Person A, sky mapper: navy coat worn long, silver scarf at the neck. Silhouette is a tall narrow column.
Person B, bed keeper: green jacket, canvas bag on the body. Silhouette is shorter and wider at the hip.
Reusable: navy coat, silver scarf, green jacket, canvas bag.
Optional purchases: none.
Neither person is a prop. No masks, no weapons, nothing revealing is required.

Pair 2. Motif: one circle, repeated (moon, fruit, seed).
Shared story: an eclipse clerk and a seed saver meet indoors to match round things: a moon sketch and a round seed pod. Each holds their own object.
Person A: navy coat open, silver scarf coiled into one circle on the chest. Long open-coat silhouette.
Person B: green jacket closed, canvas bag held in front with both hands as their own round pouch. Blockier silhouette.
Reusable: the four owned pieces, coiled or held as above.
Optional purchases: a paper circle only if you want one. Not required. No price is known.

Pair 3. Motif: two vertical lines, night and vine.
Shared story: a comet recorder and a trellis walker were both asked to describe a path, one across the sky and one up a frame. They tell those paths side by side and never attach anything to each other.
Person A: silver scarf hanging straight down the navy coat, one pale line on a dark column.
Person B: green jacket buttoned, bag strap as a second line. Jacket-and-strap silhouette.
Reusable: the four owned pieces only.
Optional purchases: none.

Pair 4. Motif: small scattered dots (stars and seeds).
Shared story: during an indoor naming hour, Person A names dots in the sky and Person B names dots that will go into soil. Each points at their own clothing or bag, not at the other person.
Person A: navy coat, silver scarf end held out so the silver reads as the dots. Long coat silhouette.
Person B: green jacket, canvas bag open at the top as a seed bag. Wider bag silhouette.
Reusable: the four owned pieces.
Optional purchases: none. Do not buy dot stickers.

Easiest pair: Pair 1.
Tradeoff: it needs no tying, coiling, paper, or purchase, and the two silhouettes already differ (long coat versus jacket plus bag). The frost-on-leaves motif is quieter, so the shared story is obvious only if they stand where silver and green can be seen together or they say the one-line story. A crafted circle or stripe would read faster from across the room and would take more fiddling.