Anonymous Bot can: View information about the user’s identity
Is true that the bot has access to the user's information, but as described in the Terms of Service, the bot uses but do not store these inforations.
This bot does not has features for removing the messages, not even for the real sender.
Check Slack's help page about deleting messages.
To disabled the bot in a single channel: remove the bot from the channel
To completely disable the bot, you need to remove the app. Check Slack's help page.
Both. You and your team can use it for free. The bot also has addicional paid features (see Pricing section).
Not anymore. The first version of the bot was open source. You can still check its source here, but it has just the basic feature.
I'm not in this chat yet. Please, invite me first. (The invite will be public)
Before using Anonymous Bot you (or someone else) needs to invite the bot to the channel.
Inviting bots or people is a public action: Slack automatically sends a message like "
was added to #general by username."
The Team Plan has a feature to restrict access for some users.
If you got this message, it means you are in the black list (or not in the white list).
Only your team admin can change this.