In Minecraft bedrock on PC, structure blocks can export and import structures from one world to another. However, in Minecraft bedrock on mobile, this feature is blocked. this resource pack from MCPEDL (credits to Darkmine) fixes that. It is made for 1.18, but the export/import buttons work for the latest versions.

The problem is, if you try to import a structure more than once, it will load the first structure you ever imported (At least in my device and version of the game).

To import a different structure, you'll need to import it on an addon with a function to build it on your world. This app does just that (credits to Pa Technologies.) It allows you to make an addon containing one or more structures, being able to build them with the /load command and distribute them all across your world.

I hope this helps transfer your buildings and items between worlds.