Rootpath vs N2 Neutral Gray

How close are they?

ΔE 23.3, loose: different enough that you should pick on purpose. N2 Neutral Gray is noticeably darker, much more muted than Rootpath.

Can I use N2 Neutral Gray instead of Rootpath?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 23). N2 Neutral Gray is noticeably darker, much more muted than Rootpath.

Can I use Rootpath instead of N2 Neutral Gray?

The same difference applies the other way round: Rootpath is noticeably lighter, much more saturated.

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.