Is a bare ESP-TM2 or ESP-ME3 WaterSense?

No. A standalone conventional panel is not the listed weather-based configuration. Add LNK2WIFI and a Rain Bird rain sensor, then enable weather adjust.

What is the usual WaterSense trio on this shop?

ESP-TM2 or ESP-ME3, LNK2WIFI, and WR2-48. Confirm the combination on your water district's list before you promise a rebate.

RC2 is Wi-Fi native. Confirm your district's listed model. Do not add LNK2 to an RC2.

EPA WaterSense on the LNK2 path

A standalone ESP-TM2 or ESP-ME3 is a conventional controller. Add LNK2 and a Rain Bird rain sensor (WR2-48 is the usual pair) and the system meets EPA WaterSense weather-based irrigation controller criteria.