My flow is actually using pressure sensor> ADS115/i2c>RaspberryPi >Node-Red > MQTT > Indigo/MQTT/Shims....So no ESP/32s involved. (I thought you were also using this approach?).
The NCD ADS1115 sensors are hooked to RPis which are running node-red, and communicating with an mqtt server i have running on the Indigo mac (though of course this could be running anywhere - but i have it running for Shellies and a couple of other projects). Currently this is working on two different RPis, monitoring two and one tank respectively. One RPi is a 3 and one a Zero.
Using the NCD sensors makes this somewhat simpler as they have published node-red nodes for all their devices. These are available in the palette, however for some reason I had to uninstall and reinstall the NCD nodes via npm, and then do an npm rebuild before the ADS1115 would connect. I managed to connect with a generic ADS1115 node before getting the NCD nodes working.
The NCD node and hardware info is here:
https://flows.nodered.org/node/ncd-red-ads1115Installing the NCD-red-ads1115 node is meant to automatically install a configuration node (NCD-red-comm) that handles the i2c communications. In my case this was not installing happily.
https://www.npmjs.com/package/ncd-red-comm