Sort of... not in one request, but it can iterate across all channels the bot has been installed in and send the message one by one.
This is a common scenario with what Microsoft calls a notification bot or proactive bot.
The way it works is the bot connects to the Azure AI Bot Service and obtains a list of all installations where the bot has been installed. It then enumerates the list of installs sending an activity to each one.
Example: https://github.com/OfficeDev/teams-toolkit-samples/tree/dev/notification-codespaces