ΔE 26.0, loose: different enough that you should pick on purpose. Phthalo Green (Yellow Shade) is noticeably darker, more saturated, warmer than Tesseract Glow. They are different kinds of paint: Citadel Tesseract Glow is a technical paint or medium and Golden Phthalo Green (Yellow Shade) is an opaque base/layer paint, so they won’t behave the same on the model even where the colour is close.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 26). Phthalo Green (Yellow Shade) is noticeably darker, more saturated, warmer than Tesseract Glow. They are different kinds of paint.
The same difference applies the other way round: Tesseract Glow is noticeably lighter, more muted, 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 Tesseract Glow on the colour wheel See Phthalo Green (Yellow Shade) on the colour wheel
All matches: Tesseract Glow equivalents · Phthalo Green (Yellow Shade) equivalents