ΔE 17.2, loose: different enough that you should pick on purpose. Hexos Palesun is much more saturated than Cremeweiss RAL 9001.
Can I use Hexos Palesun instead of Cremeweiss RAL 9001?
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 17). Hexos Palesun is much more saturated than Cremeweiss RAL 9001.
Can I use Cremeweiss RAL 9001 instead of Hexos Palesun?
The same difference applies the other way round: Cremeweiss RAL 9001 is much more muted.
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.