EXIV2:
I did a quick look at their doc page: https://www.exiv2.org/manpage.html
I get the feeling it has a problem with microseconds? And, wow, what a list of options… I think you understand what I want/need to do, but I think I’ve faster altered the perl software I shared earlier, than that I’ve figured this out I think?
QUALITY COMPARISON YI360 vs LG360
I took al look at more images I have taken with the LG360. I more or less accidentally took a good image to compare it to, but looking with a more critical eye, I see that the LG has a lot of difficulty with the lower sun and with less daylight. The first few tests do give me the impression that the image quality of the YI seems much more stable… Therefor, in movie-grab-mode the quality may be less, compared to a good LG-image, but overall the quality of the YI seems much more stable…
Next up is working on creating a good workflow to get as good as possible EXIF data in the images.
Next to that I realy hope the Mapillary team can get rid of the error I’m getting with the app. Then I can do tests with “image mode”. And really get to work 
[update]
NEW MICRO SD CARD
Did some experimenting with my new Sandisk Extreme PRO 128GB memory card. With a timer going off every one second, it missed quite a lot of images. On 2 seconds it snapped all the 5.7K (16.6MP) images. Setting at 1.5 felt a bit unstable and it worked well at 1.75 seconds. All this done manually (beep, press button ), so an actual value will probably be around 1.5 to 1.7 seconds per image.
This means that when an “interval setting” becomes workable, this camera is fast enough for taking pictures when walking and when cycling not to fast (at 12 km/h it’ll be around 5 meters per image).
So for now I’m stuck with video mode… That gives me time to get to a good workflow processing an MP4.
But ultimately I offcourse want “the best”… and separate images have a higher quality then MP4-grabs (obviously), so I prefer an “image interval mode”.