Kaizena is a Google Docs and Slides Add-on. Kaizena’s big feature is Voice Comments. Kaizena lets you record feedback verbally to digital assignments and some teachers claim it saves them 40% of their time when grading. I can see this being an extra big help for ELAR teachers who need to respond to written compositions.
https://workspace.google.com/marketplace/app/kaizena/354175553078?pann=cwsdp&hl=en
Kaizena is allowing me to leave comments on Google Docs for free but is requiring me to subscribe to a paid account to us it in Google Slides.