Yes, it is possible to do this.
1) Enable Whisper Interaction Within Deepbot
Config Tab -> Master Settings -> Scroll down and make sure that "Enable Whisper Interaction (Bot)" is ticked.
2) Set up your command so that it can whisper the user that calls the command
With your particular case, the message you would send would be similar to what's outlined below;
/w @user@ You have been following since @followdate@
You can also make it so that the command can only be accessed by whispering the bot by unticking "Channel Messages" in the command editor. The same applies if you don't want the command to be accessed via whispers
Please note that I've been hearing on the grapevine that bots that excessively whispering have been getting shadowbanned by Twitch due to some system they have in place. This was to combat the spam bots you have probably seen around but can also take out some innocents in the crossfire.
Thanks,
Dante557