ΔE 18.5, loose: different enough that you should pick on purpose. Off-White is a little darker, much more muted, warmer than Menoth White Base.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 19). Off-White is a little darker, much more muted, warmer than Menoth White Base.
The same difference applies the other way round: Menoth White Base is a little lighter, much more saturated, cooler.
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.
See Menoth White Base on the colour wheel See Off-White on the colour wheel
All matches: Menoth White Base equivalents · Off-White equivalents