the sidebar font is the same ubuntu font, using elementary tweaks only provides Default, Document, Title and Monoscape fonts.
These settings don't change the vscode sidebar ubuntu font, and why the heck ubuntu font is there in vscode, please provide a solution
VS Code is an Electron app (built using web technologies), as opposed to a native app (using GTK). I don't believe you have any control over the fonts beyond whatever settings Microsoft have exposed in the config; and it doesn't look like there is an option to change the sidebar font.
There is a GitHub issue here requesting added support for changing the sidebar font, so keep an eye on that.
/usr/share/vscode/resources/app/out/vs/workbench/workbench.main.css
Just edit font-family CSS to get different font in sidebar
