This is how Ryan's and Meg's training and the birth of Ladyan and Kitty Noir goes in the pilot episode of Crash's, Thomas' and Ryan's Adventures of Miraculous: Tales of Ladybug and Cat Noir.
Ryan F-Freeman: So. You are saying that I can catch those Akumas?
Rikki: Yes. Plus you can transform to a Ladybug based hero.
Ryan F-Freeman: But, how will I transform into a Ladybug hero?
Marinette: Let me show you, Ryan. Tikki, spots on!
[Tikki flies into Marinette's earring and she transforms to Ladybug]
Ryan F-Freeman: Whoa. Marinette? You're...
Ladybug: Ladybug? Yeah. You think you can transform?
Ryan F-Freeman: Ok. I think all that I have to do is say "Rikki, Spots on!" and....
[Rikki goes into Ryan's braclet and Ryan transforms to a male version of Ladybug called "Ladyan"]
Ladyan: What in the world?
Crash Bandicoot: And there you got it. New costume, a yoyo and we could do some training with your Nobody friend.
Ladyan: Cool. But, you think you can train me?
Adrien: Well, Meg. In order to transform, you need to say this. Let me demonstrate. Plagg, claws out!
Roxanne (Rianna's Nobody): Whoa.