ΔE 31.5, loose: different enough that you should pick on purpose. Mortarion Green Clear is noticeably darker, much more muted, cooler than Rainforest.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 32). Mortarion Green Clear is noticeably darker, much more muted, cooler than Rainforest.
The same difference applies the other way round: Rainforest is noticeably lighter, much more saturated, warmer.
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 Rainforest on the colour wheel See Mortarion Green Clear on the colour wheel
All matches: Rainforest equivalents · Mortarion Green Clear equivalents