RetroArch aspect ratio problem

Hi. In RetroArch's video settings aspect ratio is set to core provided but sometimes I'm not happy with core options (or lack of option).
for example: I get too thin picture for PC-Engine CD (or Turbo Duo or TurboGrafx CD however you want to call it) because there is no option for aspect ratio in its core settings.
If I set aspect ratio in video settings to 4:3 I get what I want but that ruins aspect ratio for other cores which don't use 4:3 aspect ratio unless I change it back to core provided again. So I have to change AR in video settings every time I want to play Castlevania: Rondo of Blood and again for something else.

Nevermind. I figured it out: https://forums.libretro.com/t/how-to...-per-core/5743
Now if only I could have different hotkeys for different cores.

I believe it is possible for the hotkey issue, its either implemented and a little confusing to figure out or you need to use overrides.

I suggest either going to the official RetroArch forum to ask/learn or the RetroArch irc channel.

I was able to accomplish this with some manual editing of each core's cfg file.
Here is post I found that helped: https://forums.libretro.com/t/per-core-hotkeys/8784