@androidonpi The errors appears because you're running RetroPie from the desktop environment. As @dankcushions mentioned, this is not a supported configuration. On the Pi4, drastic will run by starting an X server first (as a few other ports already do), if you're already running in a desktop environment, that won't work.
drastic is not a libretro core, so the file you added doesn't have any effect on the emulator. I see that drastic has a 'Screen orientation' option, but it doesn't seem to add any rotation - maybe works only on Android (?).
Yes I have a pi 4. I did manage to make some changes to the settings it was a challenge lol. I can change the internal Drastic views on a horizontal screen. But I want the whole screen rotated 90 degrees(vertical) so when I stack the screen top/bottom it uses up most of the viewing area. Here's what I would like to achieve on Drastic. This is what my lr-desmume looks like.