Key takeaway
SecretSkies is the closest practical Bluesky edit button right now. It is not universal. It works only where a compatible third-party ATProto app, forked community, or community client chooses to show the updated version.
Why Bluesky editing is tricky
A normal edit button would change the post for everyone. That is not what Bluesky proper supports today. Bsky proper keeps showing the original version. SecretSkies works below that surface by updating the ATProto record that some other views can read.
What to do next
If you want a universal edit button, this will feel limited. If you want an edit button for a compatible community or third-party ATProto app, this is exactly the space SecretSkies is built for.