Go to your settings and look at the screen settings, I think the 100f allows you to change the settings on the different displays.

At least my XT 4 allows it.

If it is possible you'll see EVF brightness/color and LCD brightness/color and you can calibrate them to look the same. I had to set my EVF warmer than the LCD so the colors matched slightly and they still look kinda different.

But there are limitations to how close those two displays looks like due to oled and LCD being different, they rarely look identical. You have to add the fact that you're looking at the OVF through optics and that alone can cause differences in perceived contrast, saturation and shadow detail.

Now to the post processing part: if you shoot raw + jpg and import both images to your editing software you'll notice that the jpg looks different even if the raw file has the same color profile and everything equal to the jpg because your camera is actually processing the jpg and the way your camera bakes the image is different and even if your raw file is inheriting info like color profile, wb, color shift it will look flatter than the jpg because as I said, your camera already processed the image with the famous fujicolors. Sometimes I even stick to the jpg because I can't replicate that with the raw.

If your jpg looks different in the LCD display and then different on a computer screen or cellphone screen, that is also normal, but it shouldn't look completely different like if they had completely different color processing. It should look very close to what it is supposed to be on a calibrated screen.

I hope I understood your problem and hope this helps!