As the title suggests, on landscape mode screenshots taken are troubled.
ROM : PixelExperience Q October patch

This is not the issue with just only this project, same result with the original Screenshot Assistant app & also another similar FOSS app Screenshot Sharer.
But mapping assist app with Macrodroid for screenshots or using Remap Assistant module from Cometin app doesn't capture such glitched shots. As I understand these apps use different method of capturing since I get notification for the shots like I'd get if I use Android's screenshots shortcuts.
This might not be an issue with this project, rather an issue with Android 10 itself or just my ROM.