Nether Portals do not respect Overworld positions, and will instead all link up directly in the nether

1. Create a nether portal and travel through it

2. Return to the overworld, teleport about 1000 blocks away via /tp ~1000 ~ ~1000

3. Create a new portal and travel through it

4. You will go through the old portal, and not a new one

Video: https://streamable.com/t8kcn