The "Personal" plan fits for users who want to activate the feature for their accounts only and they are charged only for one user. You can subscribe at a personal account (Sign-In).
"Team" plan
The "Team" plan makes voice messages available for all users in the Slack workspace (for current and new).
We charge a fixed price for Slack workspace per month (not per each user). Only the user responsible for your team pays. Usually, this user is the manager of the team.
14 days free trial for TEAM plan, no credit card required
Check out our FAQ for more information