@Wannikea ********
Thanks for claryfing. Now I remember I once requested a statement of salary where they also included that I'm currently employed an such. It had a different name but I think that's what one would desribe as a 'certificate of employment' (even though the term 'certificate' is kinda funny for a document with a couple lines of text saying I work there haha). I think that's the closest I can think of. Which is indeed different from my employment contract. 🙂
The Taipei embassy told me, if I show the business licence for the company in my name, it's enough. So I'm kinda lucky I suppose. 🙂