The error was found under the following conditions:
1) The game was launched on an android device. (device: Redmi Note 12)
2) It was in a single world without the Realm signature, without mods, addons and additional textures.
3) All portal coordinates in two worlds were shown in the game screenshot.
4) I did not use any commands in the game world.
5) I just created a new world with the following modified settings: difficulty: hard, cheats: enabled, seed: random, game mode: creative.
The portal was faulty, just like last time. Namely: when you first enter the portal at coordinate Z, the portal in the lower world is generated at coordinate X. Because of this, the player is teleported turned 90° to the portal. (as shown in the screenshot)
This is all the information I can tell you.
Sorry, but I can't send you screenshots, but visually it is exactly as I described in the previous comment.