I want to connect each repository on GitHub to publish notifications on its respective channel on Slack. For example:
github:repoA >> slack:channelA github:repoB >> slack:channelB
Is it possible?
Yes, it is possible.
You need to install the application of GitHub in your Slack, and add a configuration for each channel that you need to connect with GitHub. You can have more than one GitHub repository connected to one channel in just one configuration. But if you want to connect the same GitHub repository to differents channels you need to add two configurations for each one.