How to correctly form an expression replacement query?

Question

bash

here is my expression

grep '<a class="catalog-box__link" href="/"><i' -P -R -I -l  * | xargs sed -i 's/<a class="catalog-box__link" href="/"><i/<a class="catalog-box__link" href="##"><i/g'

here are the errors
sed: -e expression #1, char 44: unknown option to `s'
sed: -e expression #1, char 44: unknown option to `s'
grep: krasnodar/public_html/cgi-bin/php4.cgi: No such file or directory
sed: -e expression #1, char 44: unknown option to `s'

Answer 1

So cross both of these options:

grep '<a class="catalog-box__link" href="/"><i' -P -R -I -l  * | xargs sed -i 's|<a class="catalog-box__link" href="/"><i|<a class="catalog-box__link" href="##"><i|g'

Answer 2

Did you mean it?
https://sed.js.org/?gist=c706a59d83d88852267bbe652...
If yes, then you did not take into account the specifics of escaping special characters in sed, I described this in more detail on the wiki.
If not, then give the original task.