should i use multiple country code top level domains for my website?

I live in Germany and I am currently trying to create an online shop at Shopify for my business. I have some offline customers which are mostly located in Germany, but also in Switzerland and Austria.

I own all country code domains, for example (generic names):

• test.de --> Germany

• test.ch --> Switzerland

• test.at --> Austria

However, I also own test.com.

My question is now, what domain I should use? Is it better for SEO reasons to use all country-specific domains? This means that I will have 1-Website and depending on the country, I show a a different domain. For example my users in Switzerland will be redirected to the ".ch" domain. I this actually possible? I am not sure if Shopify allows me to configure this?

Or should I use .com - domain?

I did some research, however there seem to be different opinions on this topic.