I don't own any mf lenses, but this is almost too tempting to pass up. How big of a deal is manual focus in M43-land?? GX85, if that matters...
https://ttartisan.myshopify.com/products/aps-c-25mm-f2
I own both the TTArtisan 17mm f/1.4 and the Samyang 7.5mm Fisheye, both are manual focus. It’s not a big deal to manually focus them as M43 gives you the ability to focus peak and magnify your focusing area to get more precise focus. The LUMIX implementation is slightly better, in my opinion, than the Olympus. I own both LUMIX and Olympus bodies.
Having said that, the reason the TTArtisan lenses are cheap is because, they are not clinically sharp compared to the Panasonic or Olympus 25mm version wide open though and usually, you have to stop it down to f/8 to get good sharpness. Lens flare is another issue with the TTArtisan lenses as they flare a lot if you shoot in direct sunlight. Otherwise, if you don’t mind a little bit of softness wide open and a bit of lens flare, I found that my own TTArtisan 17mm is a great deal for what it is. It does have its own color character though, a bit old school Zeiss Sonnar lens color rendering which is why I love my TTArtisan 17mm, not because it is 17mm, but because of the character itself gives to the photos.