Do you know of a database of fonts that lists fonts by feature?

Specifically, I am looking for a font that is monospaced for character-width but allows for thin spaces. To be even more specific, I have a project that needs to display columns of hexadecimal numbers, but I want to separate groups of digits with thin or half-width spaces. So I need the characters 0-9,A-F or 0-9,a-f, to be all the same width but thin spaces, (e.g. Unicode \u2009, or another narrower space could be ok, too) to be a shorter width.

Any ideas would be greatly appreciated.

As far as I know, no such database exists (sadly, not least because it would be a valuable resource for font IDs).

However, I know of many “semi-monospaced” typefaces that could help you achieve your goal. Here are some that come to my mind presently (but there are many more): Trispace; Lekton; Input; Iosevka; IA Writer.

Additionally, depending on the software used, it could still be possible to insert an half-width space even using a fully monospaced font.

Trispace and Lekton do the trick. (The others are not apparently readily available in my system.) 

Thanks so much!

Here's Lekton, exactly what I needed.