Hi Amber,
I also did my 190 visa while living in a different country than my homeland. However, I have lived here all my life, so it was easy for me to arrange for all documents required - educational, work-related etc.
It doesn't really effect your process. Your documents can be certified in the country where you're residing, regardless of your country of origin. Just make sure that you have all required documents when you start the process, or you can arrange it easily.
All the best!