PNG imports lose clarity upon editing

Hey,

I am currently tackling a project that involves animating PNG files imported from an Illustrator file. Initially, I attempted to import the AI files via the library, but encountered issues. Due to time constraints, I opted to import the layers as PNGs instead. Now, I can proceed with animating and coloring them as needed.
Is there a method available to maintain the sharpness or preserve the UK Solar Compare original quality of the images? Additionally, the blurriness persists even in render mode.

Thank you for your reply.