Yes, there are just a few variable OpenType fonts installed (I count 7). The specification was announced last year so things are still early. You can look here for more info on updates: The Typekit Blog | Variable font technology from Adobe
Thx for the reply.
Where does Skia Black come from?
does Typekit have any other variable fonts? (I couldn’t see any when I looked, but may have missed)
That is just 'Skia' actually and it is included in macOS, I believe. I don't know what Typekit currently has, but I can't find anything there either. Maybe ask them on twitter?
Photoshop CC 19.0 ships with 6 Variable fonts (not all Adobe fonts are variable fonts), please see the list below. We have a new icon in the font menu to identify variable fonts. At the moment we don't have any more Variable fonts on TypeKit Server. Skia is a GX Variation font which predates OpenType-Variable font spec.
Variable fonts and Axes list
Acumin Variable Concept ( 90 named instances )
Weight, Width, Slant
Myriad Variable Concept
Minion Variable Concept
Weight, Opitcal Size
Source Code Variable
Source Sans Variable
Source Serif Variable