Overall, the Eminance in Shadow manga adaptation is quite true to the original. There are some minor tweaks for better visualization and flow, but the core elements remain intact.
Battery car cartoons usually have colorful and cute designs to attract kids. They might also show various adventures and challenges related to battery cars.
It could be that the creators wanted to show a special moment of connection between the characters. Or perhaps it's a part of a larger theme or message the cartoon is trying to convey through these kinds of images.
The copyright for Sonic comics is usually held by the publisher or the company that created the Sonic franchise. It's a complex matter involving various legal and licensing agreements.