You asked

Is the leica cl good in low light?

Here is what the site says about that.

From Leica CL: Leica CL: A mirrorless camera by Leica with a 24-megapixel APS-C sensor, announced in 2017. A small APS-C body with a built-in viewfinder and dials; takes TL and SL lenses. Specs - Maker: Leica - Mount: L-Mount - Sensor: APS-C, 23.5 x 15.6mm, crop factor 1.5 - Resolution: 24 megapixels - Stabilisation: none in the body; use stabilised lenses for slow shutter speeds - Announced: 2017 - Type: mirrorless camera Focal lengths ...

From Leica SL2-S: Leica SL2-S: A mirrorless camera by Leica with a 24-megapixel full frame sensor, announced in 2020. The 24-megapixel SL2, better suited to low light and video.

Quoted from this site's pages.

From these pages