Most definitely, you can add as many Google Analytics accounts as you want!
How to add a Google account
Sign into Arc Analytics
Select Accounts from the top menu on the dashboard
Select + Add to add another Google account
When you add a Google account, you will be redirected to Google to select an account and then redirected back to Arc Analytics. This guarantees that Arc Analytics can never access your Google account's login info.
Google account security and privacy
Each account is private to you, so the only Google Analytics account information visible to your team is what you associated with a report.