A Journey into the Mysteries, Starting with Harry Potter

The following synopsis:

In his seventh year after transmigrating into the world of Harry Potter, Chen Yuan finally received an offer to become Hogwarts' Professor of Muggle Studies. But after waking up one morning, he discovered that he had transmigrated yet again.

This time, he had ended up in a woman's body.

At the same time, Bernadette, the "Queen Mystic," awoke in Chen Yuan's body.

P.S. The male and female leads swap souls every few days.

The synopsis for this story:

Edward has transmigrated again-this time into the world of Lord of the Mysteries.

From that moment on, this world has one more outsider: someone who can regularly travel between two worlds.

What will he bring to both of them?

P.S. 1: This is a traditional fanfiction, so the story will not completely sideline the original characters. The female lead is Miss Justice, and the Queen may join her later.

P.S. 2: The protagonist's Beyonder pathway is partially original. He follows the Apprentice pathway early on, with changes beginning midway through the story.

P.S. 3: The protagonist is virtually invincible against opponents at the same Sequence, but he cannot simply slaughter higher-Sequence opponents left and right.