BACnet gateway to emulate existing devices that are being decommissioned

Hello. We have a very old (un-editable) application that talks to a handful of BACnet devices that we are decommissioning. We’d like to keep this legacy application running by using a gateway of some kind to emulate the existing devices by using the same device and object IDs. Is this possible and if so can anyone recommend a device that can do this? Preferably it will get translated into modbus or mqtt for use in Ignition.