Matt Black Primer vs Mordant Earth

How close are they?

ΔE 24.8, loose: different enough that you should pick on purpose. Mordant Earth is noticeably lighter, much more saturated than Matt Black Primer.

Can I use Mordant Earth instead of Matt Black Primer?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 25). Mordant Earth is noticeably lighter, much more saturated than Matt Black Primer.

Can I use Matt Black Primer instead of Mordant Earth?

The same difference applies the other way round: Matt Black Primer is noticeably darker, much more muted.

ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.