4:3

I want to shoot a project with a 4:3 aspect ratio.
Is it possible to display a 4:3 image while enabling the anamorphic mode (But not using an anamorphic lens)?

Not that I’m aware of. You can either get a monitor that can squeeze the image back or shoot with the full sensor and use 4:3 guide lines.

Save recording some potentially wasted horizontal resolution and shoot UHD 3840x2169 with the 4:3 guide in camera as suggested by Adam. In post, select your timeline resolution as 2880x2160 for example. Then in post you can reframe on the horizontal X axis by plus or minus 480 pixels.

Thank you.

What resolution will be the resolution for your deliverables? I assume you’re shooting with 2x anamorphic lenses.