See discussion here: https://community.adobe.com/t5/adobe-fonts-discussions/allow-css-font-weight-to-be-used-with-variable-fonts-by-putting-the-full-range-in-font-face/m-p/13539383#M7419

Summary: when serving variable fonts via CSS, Adobe specifies their font-weight as 400 instead of (say) 100 1000 in the @font-face declaration, which means the font-weight CSS property cannot be used to change these fonts' weights; you must use, say, font-variation-settings: "wght" 700. Ideally Adobe would use 100 1000 as the font-weight in the @font-face declaration so that users could use font-weight in their CSS to change the weight of a variable font.