Unfortunately, there is no such feature in Figma. But feel free to leave your feedback and vote in this thread: Add a glyphs panel please.

Thank you!!!

Hi! I’m not sure if this works only for Google Fonts, but I was figuring out how to get the alternative numerals for Mansalva and four out that you have to type the same alphabet/number consecutively and it will reveal the glyphs. Hope that helps anyone!

This method seem to only work on the Figma desktop app btw

In case anyone hasn’t figured this out, in the type settings panel under “details” tab (as opposed to the “basics” tab), you can find your alternate stylesets. It’s not right in context like adobe, and you can’t seem to set a font style with only one character for instance (in my case the lowercase “g”). I just had to select my “g” every time to get my alt character. But it’s there.