None of Apple platform built-in font support both italic-smallcap features combination. System San Francisco is the most font-feature capable font supports smallcap for regular and bold, but not for italic.


Small caps are rare feature, and rare fonts support it, but even more rare, unique, fonts support both.
Here is quotation from Wikipedia ref.. pay attention on last sentence.
Small capitals are not found in all fonts, as they were primarily used
within body text and so are often not found in fonts that are not
intended for this purpose, such as many sans-serif families.[6] Some
font families, especially digitisations of older metal type designs,
often lack small caps in bold or italics, only having them in the
regular or roman style.[7] This is because they were normally only
used in body text and cutting bold and italic small caps was thought
unnecessary.[a]
See also:
AHIG Typography