It is possible to add another driver, but it takes some effort and time. Estimated costs can be 900-1200 €. If necessary, please contact firstname.lastname@example.org.
In the SoftPLC IDE, basically nothing is set in the channel properties, the key properties are the OID (must be known, you can find out by SNMP browser) and of course the IP address or hostname (if the PLC has a DNS server set up) of the SNMP device (UPS).
Complete descriptions of variables for specific UPSs can be found here.