I will explain how to recreate it:wear an elytra and fill your hotbar with random objects but in one put a trident with riptide3 then put a random item in your second hand and activate alytra while jumping in water then use the trident(while the elytra are still open in the water)and quickly switch to another item in your hotbar the item will stay in a horizontal position and the second and will do that too.sorry for not having a video.