After Effects export with Renderlist much darker and being cropped with Media Encoder

Hey everybody!
So I have two problems with exporting my videos.
When I export with the renderlist, the final video is much darker than the composition in After Effects.
After that I tried to export my video with Media Encoder and stumbled upon a new problem. My 1080x1080 video was flawless but as I tried to export the 1080x1920 version, it was cropped...

As you can see here:

Thanks in advance!