The image is part of a video called "Ganyu PV without Voice Over".
The image was originally 1200 x 630. I do not recall 100%, but it could be that I found the image on the net and it's not a screenshot of the video itself. (The image looks too high a quality to be a mere screenshot of a video)
I blew it up to height of 1080 and cropped it to width of 1920 (It would have been width of 2057 otherwise). Using mtpaint I also used its Unsharp Mask - Radius 5.00, Amount 0.30, Threshold 0, [x] Gamma corrected.
This time I am quite pleased with the results.
And thanks to gnintilgyes most likely again spoiling the fun for everyone, no link to the full sized wallpaper as resized, cropped and unsharp-masked.
But using mtpaint you can easily do it yourself.
(When you can find the original, that is.)
Added in 7 minutes 77 seconds:
In comparison, this is what the original looks like (like explained above,
only a small preview thanks to gnintilgyes)

resized to a mere 400x210 px - originally it's 1200 x 630.