The background has a 0 with a lowered opacity.

By @Stefan Cargoski
Whether you find the typeface or create it yourself, it is not a zero with a lower opacity. I just checked my digital clocks and none of them do this anymore, but I remember when all of them did. The faded character is actually an eight, not a zero.
In the early days of digital clocks, the lights needed for all of the digits were slightly visible in the background, then were lit when it was their turn. Note that in your screenshot, the zero has a faded line across it that is necessary for the 2, 3, 4, 5, 6, and 8 to display.
In your second image, the one would not be centered in the zero (or eight), as a light does not exist in the center. It would be using the light on either the left or right side of the digit.
Be sure to include that horizontal light (line) if you create this yourself!
I found this on Adobe Stock. It's vector and needs to be opened in a vector application such as Illustrator.
https://stock.adobe.com/images/digital-display-font-alarm-clock-letters-and-numbers-electronic-alphabet-and-retro-calculator-screen-symbols-vector-set-lcd-monitor-and-scoreboard-digital-abc-characters/325418078

Jane