What about Sigma MC11 EF adapter ?

[frame-it]

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https://www.sigma-global.com/en/download/lenses/firmware/

https://www.sigma-global.com/en/download/lenses/sigma-optimization-pro/

and the MC-21:

Lens data is pre-loaded
Running the data pre-loaded in the MC-21 for each lens by the special control program, autofocus and aperture control have been optimized. Regarding lenses to be released in the future, data for operating these lenses via the MC-21 will be stored in the lens. It means no firmware updates of the MC-21 will be required to use those new lenses. In addition, the MC-21 also supports correction functions of camera such as peripheral illumination, chromatic aberration of magnification, and distortion.

[AlanYWM]

4 hours ago, frame-it said:

https://www.sigma-global.com/en/download/lenses/firmware/

https://www.sigma-global.com/en/download/lenses/sigma-optimization-pro/

and the MC-21:

Lens data is pre-loaded
Running the data pre-loaded in the MC-21 for each lens by the special control program, autofocus and aperture control have been optimized. Regarding lenses to be released in the future, data for operating these lenses via the MC-21 will be stored in the lens. It means no firmware updates of the MC-21 will be required to use those new lenses. In addition, the MC-21 also supports correction functions of camera such as peripheral illumination, chromatic aberration of magnification, and distortion.

This is only applicable for new lenses. Firmware upgrades may still be forthcoming for existing lenses to improve AF and other functionalities like lens IS. At least that is what I am hoping 😀