ΔE 18.4, loose: different enough that you should pick on purpose. Hellspawn Red is noticeably lighter, much more saturated, warmer than Resplendent Red.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 18). Hellspawn Red is noticeably lighter, much more saturated, warmer than Resplendent Red.
The same difference applies the other way round: Resplendent Red is noticeably darker, much 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 Resplendent Red on the colour wheel See Hellspawn Red on the colour wheel
All matches: Resplendent Red equivalents · Hellspawn Red equivalents