I don't get it... what's the difference between Chris "Shadowheart" Corona and Chris "Yuushi" Corona besides their nicknames (or middle names)?
The middle names are cursor marks to tell which universe each of the Chris comes from, Chris "Yuushi" Corona comes from the "Virakins" universe which is my main and original series while Chris "Shadowheart" Corona exists in the "LaTale" story universe (where he lives in a different version of the world "Magleutix" which is an alternate version of the "Virakins" universe's "Magleutix").
The two Chris differ with their personalities, how they live their life, changes to the family (in some universes Chris is either an only child, has a younger sister (most of the time), and has both an older and younger sister), different fighting styles and abilities, different friends and love interests (Ami Rozu for the "Virakins" universe and Iris Livier for the "LaTale" universe), etc...
Kinda like the Amazing Spider-Man and Ultimate Spider-Man series.
Chris "Shadowheart" Corona (I really need to give a better middle name for this one) has a childish, outgoing, blunt personality and acts impish and excitable with his pranks and tease, but has mature and understandable side underneath due to the way he lived his life. This Chris was "born" with the Virakin powers, or power of darkness as the people refer to it, unlike the Chris from the "Virakins" universe where he merges with the Virakin power later on in his life. He has no parents or siblings and only an uncle (or his Chris' mentor in the "Virakins" and is not his uncle in that world) and great-grandfather and hardly has any friends at the start.
Chris "Yuushi" Corona is a sweet, shy, uncertain young man that takes things easy and cherishes his friends but questions himself about what the right thing to do and is still learning and growing up though his cheerful side shines though. He gains his Virakin powers later and his has great potential, but he's sadly weak and cannot bring out the full powers of a Virakin which is why he struggles a lot in his fights but doesn't give up. Has parents but are currently aware, has a younger sister, childhood friends with a princess Oni and elven girl along with his best friend Alvin (who is Chris' best friend in almost all universe he appears in) and a red-haired chinese girl named Raine.
But there are things that are reflected between each version of Chris... they never take a life no matter how evil or bad a person or being is, also has a naive and optimistic outlook on life as well as try to understand from both sides of the story to make a fair judgement, has a huge appetite (common for Shonen heroes), always manages to put a smile on their friends faces, never abandon someone in need. Stuff like that... it's more easier to show off his actions than writing.
And each universe has a different story to tale about each Chris.