From the answer to a related question I know it's possible to batch clone repositories based on a GitHub search result:
# cheating knowing we currently have 9 pages
for i in {1..9}
do
curl "https://api.github.com/search/repositories?q=blazor+language:C%23&per_page=100&page=$i" \
| jq -r '.items[].ssh_url' >> urls.txt
done
cat urls.txt | xargs -P8 -L1 git clone
I also know that the Hub client allows me to make API calls.
hub api [-it] [-X METHOD] [-H HEADER] [--cache TTL] ENDPOINT [-F FIELD|--input FILE]
I guess the last step is, how do I archive a repository with Hub?