Sigma L lenses

Sigma Art lenses are supposed to be sharp. Also big and heavy. I see they have come out with a new version of their fixed focal length lenses that offers external f-stop adjustments. Also the lenses are lighter, but apparently without some of the built in lens correction. Instead they rely on the camera that is attached to the lens to do the correction. Is this something that works with the cinema camera (I don't think so) or Davinci Resolve (maybe?)

They have a 35mm f/1.2 L mount that is interesting, but not if the needed lens correction doesn't work with our cameras.
Sigma Optimization Pro perhaps. Has anyone used this with BM cameras?

BM cameras don't do any lens corrections.
But if you think about lens shortcomings like vignetting or distortion, DR can cure that.

Is there a database of various lenses in Resolve to correct individual lens anomalies, or can they be added as new lenses become available?

Sigma Art lenses are supposed to be sharp. Also big and heavy. I see they have come out with a new version of their fixed focal length lenses that offers external f-stop adjustments. Also the lenses are lighter, but apparently without some of the built in lens correction. Instead they rely on the camera that is attached to the lens to do the correction. Is this something the works with the cinema camera (I don't think so) or Davinci Resolve (maybe?)

They have a 35mm f/1.2 L mount that is interesting, but not if the needed lens correction doesn't work with our cameras.
Sigma Optimization Pro perhaps. Has anyone used this with BM cameras?

I would stay away from mirrorless lenses for the reasons you highlight.

Mirrorless lens manufacturers rely on a combination of in-lens and in-camera corrections (which are not baked into BRAW) to deal with things like distortion, vignetting and colour shifts between the centre of the image circle and the edge of the image circle.

The colour shifts in particular are a pain to correct in post and a common problem with mirrorless mounts because of the short flange distances, where the light at the edge of the image circle is hitting the sensor plane at an extremely acute angle compared to the centre.

I have experience of using poorly corrected lenses with the BMCC6K and it is a pain to get right in post.

However, I picked up the Sigma DG HSM ART range originally designed for DSLR and which Sigma converted (with an integrated mount converter) for L-Mount. They really are spectacularly corrected, the 28mm and 40mm f/1.4 DG HSM ART in particular. The price on the used market is also great value.

I second those ART lenses by Sigma, they are up there with the best. Of course, those integrated adapters are only adapting flange distance and electronics, they are not correcting anything like in-camera processors.
So, with those you are looking at honest optical quality.

I got a deal on an EF 24 f/1.4 L II lens, and am looking for some other fast primes. I like the Sigma EF Art variety, so I can use them with an L adapter and still use them on EF cameras including the older BMPCC bodies if I want to. I do have converters, including the Sigma EF-L converter. Used they seem to be an equal or better deal than comparable EF glass. Anything to look for when buying them?

I got a deal on an EF 24 f/1.4 L II lens, and am looking for some other fast primes. I like the Sigma EF Art variety, so I can use them with an L adapter and still use them on EF cameras including the older BMPCC bodies if I want to. I do have converters, including the Sigma EF-L converter. Used they seem to be an equal or better deal than comparable EF glass. Anything to look for when buying them?

I would consider looking at getting the 28, 40, 85 or 105 first if you're looking at the photo versions. There's considerable differences in optical quality between the early releases (35mm) versus something later (40mm).

I personally love the Sigma 28/40 and find that they pair exceptionally well with the 12Ks (both the UMP and especially the Cine 12K).