Hi @MetroExpert,
SNMP directly to ONT is not possible. You can configure SNMP on OLT and connect ONT to the OLT. You can also manage ONT through the WEB interface, or Huawei NMS.
To configure BRIDGE mode:
In the navigation tree on the left, choose WAN > WAN Configuration. In the pane on the right, click New. In the dialog box that is displayed, set Mode to BRIDGE,
Figure 1 WAN Configuration - route(IPv4) In the navigation tree on the left, choose WAN > WAN Configuration. In the pane on the right, click New. In the dialog box that is displayed, set Mode to Bridge WAN, as shown in Figure 3-5.
Figure 3-5 WAN configuration - bridge
Click Apply to apply the configuration.
Below a example to configure Service-profile to BRIDGE:
https://forum.huawei.com/enterprise/en/service-profile-bridge-ont/thread/756601-100181
i hope it helpful!