Header modifications

We support the K-12 Zscaler education community in NC.

Our folks would like for Zscaler to be able to do header modifications to support features such as Creative Commons image search.

Examples would be adding strings to popular search engines to display only copyrighted images licensed for re-use:
bing “adlt=strict&qft=+filterui:license-l2_l3”
yahoo “vm=r&imgl=fmsuc”
Google “tbs=sur:fmc&safe=active”
duckduckgo “kp=1”
yandex “fyandex=1” or “family=yes”

A number of competitors such as iBoss, Securly, Content-keeper, and Lightspeed offer this.
This is a big deal for the schools (there are not many racy copyrighted images online).

We have had an enhancement request in for header modification for 5+ of the 10 years our sites have been on Zscaler.

Is there anyone other than NC schools wanting ability to do header modifications in Zscaler?

Thanks!