Thanks
> It looks like Gaussian blur. Probably "deconvolution" can fix it. Random link from Google: https://www.ianmorison.com/deconvolution-sharpening/
After a quick search, the Smart Sharpen I used along with setting the remove dropdown to Gaussian Blur, does indeed deconvolution sharpening.
Will try the same in Lightroom & CameraRAW which the author suggests may have better results. [1]
[1]: https://gregbenzphotography.com/photography-tips/what-is-dec...