I want to go independent from the United Earth commonwealth but Im not sure if I'll be able to trade after. Can someone tell me what happens?
I'm afraid you're not in the correct section of the forum. This is the Ape Apps forum, the My Colony forum is here
https://www.ape-apps.com/viewpage.php?p=20.
To answer your question,
yes, you can still trade after independence just like before.