https://jigarius.com/blog/multiple-git-remote-repositories#push-to-multiple-remotes

git-mutliple-origins.ps1

# Push to multiple remotes
# To do this, choose a remote ID which will refer to all the remotes. 
# I usually call it all, but there are developers who prefer origin. 
# The idea is to add all the remote repo URLs as  “push URLs” to this remote.
# Here’s what you do:
# Create a new remote called "all" with the URL of the primary repo.
git remote add all git@github.com:jknopp/toggl2redmine.git
# Re-register the remote as a push URL.
git remote set-url --add --push all git@github.com:jknopp/toggl2redmine.git
# Add a push URL to a remote. This means that "git push" will also push to this git URL.
git remote set-url --add --push all git@bitbucket.org:jknopp/toggl2redmine.git

# If you don’t want to create an extra remote named all, you can skip the first command 
# and use the remote origin instead of all in the subsequent command(s).

# Now, you can push to all remote repositories with a single command!

# Replace BRANCH with the name of the branch you want to push.
git push all BRANCH

#--------------------------------------------------------------------------------------------------#

# Pull from multiple remotes
# It is not possible to git pull from multiple repos. 
# However, you can git fetch from multiple repos with the following command:

git fetch --all
#This will fetch information from all remote repos. 
# You can switch to the latest version of a branch on 
# a particular remote with the command:

# Checkout the branch you want to work with.
git checkout BRANCH
# Reset the branch to match the state as on a specific remote.
git reset --hard REMOTE-ID/BRANCH