Remote is about TRUST.
If you aready hired them, you must trust them. Trust them on day 1. If you trust them, they will trust you back. This is how best work happen.
Most of people are trustworthy. If they went through your interview processes, you still cannot trust them, fix your interview processes.
Build trust by having a transparent culture that everyone can access almost everything.
A way to think about Trust is Trust Battery by Tobi, CEO of Shopify.