Futaba Sakura speculates that Akechi was only able to awaken to two Personas (one that represented his lies and one that represented his hate) because he didn't trust anyone enough to form genuine human bonds, implying that a person needs to be connected to others in order to make full use out of the Wild Card ability.

How does akechi have a Persona?

Akechi claims he entered the Metaverse a month before, and awakened to his Persona when he was attacked by the black masked man who killed Okumura. Akechi says that his overwhelming need to find the truth and share it with the world was what caused him to awaken to his Persona, Robin Hood.

Is akechi a Wild Card?

Persona 5 Royal but Akechi is a true wildcard - YouTube.