No
What does Mary sue mean?
A Mary Sue is a fictional character, usually female, who is portrayed as unrealistically perfect and lacking flaws. The term originated in 1970s Star Trek fan fiction and has become embedded in culture. Mary Sues are often found in fan fiction, but can also appear in published books.
Some characteristics of a Mary Sue include: Competence** They are skilled in many areas and quickly become proficient at anything they try
Ooo I didn't know this either! Learning new things everyday...
Baby Tyrant, as the title suggests, is tyrannical in her own ways, I think that's enough to be not a Mary Sue. Although I think she's not one, she has enough power and influence to be considered close to one. It's an isekai so her emotions, thoughts, actions, and decisions are mature for her age.
She's very entertaining, including those around her, and that's rich coming from me because I've read too many stories of isekai-d to babies and I've dropped most because they're boring.
This just made me realise that Barbie is a Marie Sue (the only one globally accepted)
question before i start, is the MC a mary sue