It is possible to wire 2 Doorbells in the same electrical installation, however the wiring can differ depending on the configuration of your chime.
In addition to the wiring diagrams, please make sure your chime and transfomer follow the electrical requirements:
Voltage compatibility: from 16 V to 24 V
Transformer specification: minimum 16 VA
Note: Put the power back on when both Doorbells are correctly wired and plugged on their wall mount.
Chime with Front-Trans-Rear terminals