knowledge - Find this cartoon

From the pictures below, can you find the cartoon character?

EDIT: Edited the 3rd picture for clarity

HINT 1

A scientist

HINT 2

Changing from old to new - one word

HINT 3

Even the highlighted words lead to the answer!!! $$$$

Answer

From the beginning I have a feeling of this answer but I don't know how to relate with the first picture.

My guess is, I used to love this cartoon,

Ben 10

The first picture:

Mentioned by OP, it means "accelerate" a.k.a "XLR8". Ben can transform to this alien with his omnitrix.

The second picture:

It's "transform", Ben can transform into 10 (actually more..) aliens. It can also means "upgrade" -- confirmed by OP, one of the alien names.

The third picture:

The comet, where he gets the omnitrix. May also represents aliens or outerspace tho.

The first clue:

I also don't know, Ben is not really a scientist, but Benjamin Franklin is.

The second clue:

Indeed, it is "transform" or "upgrade".

The third clue:

Man of Action Entertainment is the studio making Ben 10.