Even though Apple offers Family Sharing for apps with subscriptions and in-app purchases now, it's not available in 1Blocker yet. This feature has become available for us relatively recently and supporting it still requires a lot of additional work on our end. We will add Family Sharing support in the future, but it's hard to give any specific time-frames right now.
At the same time, you can share 1Blocker with any personal iOS and macOS devices running under your Apple and iCloud accounts.