I think Charger.

Nom en français Charlie

I don't know much about the spinoff, but I do really like Charger's design, so I went with him.

At the time of typing this, Mix is 25%, Wheeler's at 33%, and Charger's at 42%. Motor is... 0%? Dang, do folks not like her or something? (I haven't seen much of Rubble & Crew, so I know nothing about the character. I'm legit curious.)

Charger

@MarshallPupFan It may be due to her mannerisms and behavior. She is the youngest of the crew, only speaks in the third person, and has a very limited vocabulary that is usually just her saying, "Motor go BOOM!". This may be annoying to some people? But I don't think she's the least favorite, at least outside of this wiki...I think others just like the usual four (Rubble, Charger, Wheeler and Mix) more than her.

She also falls into the "secondary" category, in which she isn't seen in every episode just like Grandpa Gravel and Auntie Crane, so that could possibly be another factor.

Mix

@Lullabees Thanks for the explanation! If that's the case, then it's a shame to hear. Granted, I've only seen two episodes, but going by what little I've seen, I thought she was kind of cute.