Ok, then maybe some pre-recorded messages...
You download a plugin, copy the URL.
Go to the Plus! icon on a
conversations, send a pre-recorded message, Edit the Quick Text list...
Move with the arrow (right arrow) until you find a blank form (all fields empty). Set a message like:
Download "Plugin Name" Plugin from "the URL".
Assign an alias like /pluginname, and below that you would see instrucions on how else you could call the Quick Text.
In a conversation with a friend just type /pluginname and the message will be displayed