Karak Stone vs Beige

How close are they?

ΔE 16.2, loose: different enough that you should pick on purpose. Beige is noticeably lighter, much more saturated than Karak Stone.

Can I use Beige instead of Karak Stone?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 16). Beige is noticeably lighter, much more saturated than Karak Stone.

Can I use Karak Stone instead of Beige?

The same difference applies the other way round: Karak Stone 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.