Here’s a shortcut I wrote that converts TSV to a Markdown table. It doesn’t do any of the fancy alignment stuff, but it does try to make the resulting table look decent via proper padding. Also, it doesn’t use any Mac specific scripting or third party shortcuts so it should work out of the box across Apple’s platforms.
https://www.icloud.com/shortcuts/edc32594a7f7476aba76f32de7176988