Mustard on cool, light skin tones (Light Summer)

The answer

No. Mustard sits well outside the Light Summer palette. The nearest thing in the palette is #E8E6E1, ΔE 29.9 away, which is one of the four neutrals the season is built on. Under 12 reads as the same colour family; past 25 the two are visibly different colours.

It does not collide with anything on the season's avoid list, so the only question is distance.

How mustard scores across all twelve seasons

Mustard is an opinionated colour: True Autumn scores it 81 and True Winter scores it 0. A gap that wide means the colour genuinely decides something, and getting it right is worth the effort.

Light Summer sits 9 of twelve at 25, 56 points behind True Autumn. That gap is the honest size of the compromise, not a verdict on the colour.

• True Autumn: 81 (ΔE 7.6).
• True Spring: 79 (ΔE 8.4).
• Bright Spring: 75 (ΔE 10.0).
• Light Summer: 25 (ΔE 29.9) <- this season.
• True Winter: 0 (ΔE 34.1).

What to wear instead

Nearest first. These are the colours in the Light Summer palette that get closest to what you wanted from mustard, so the substitution costs the least.

• #E8E6E1: very light, a white (ΔE 4.9).
• #C4C6C9: light, a white (ΔE 11.8).
• #AAC8B8: light, nearest common name grey (ΔE 17.8).