Automate is governed by the same security and permissions model as the rest of the platform. Users can only see and interact with the automations to which they have access. This ensures condition evaluations and effects always reflect the appropriate data access at the time when the automation is evaluated.
When you edit and save an automation, you may have the option to become the automation owner (taking ownership from the previous owner) or to keep the original owner. You must take ownership of the automation to make edits to the condition or effects.
Future actions effects will execute on behalf of the new owner.

A Sales Opportunity object type uses a restricted view. Users have different permissions: some can access sales opportunities from Europe, others from the US.
You can configure an automation to notify users when new Sales Opportunity objects are added by using an Objects added to set condition. When a new opportunity from Europe arrives, the condition will be evaluated per recipient.
Europe will not see any activity on the automation; no condition event appears, no notification sent.Europe will be notified as expected.