I have my own private dedicated bedrock server for a group of friends. Two of them play on the PS4 (one of them doesn't even have a laptop at the moment, broken), and they were not able to connect to our server since PS4 doesn't support that at the moment.
I created a small app over the course of a couple of days to help them out. It will proxy an external dedicated bedrock server into the local network, so the server shows up on PS4 as it would be on your LAN. You will be able to find the server under "Friends" and "LAN Servers" instead of the (non-existent) server tab.
You just open the app, type in server address (and port if not default) and click start. PS4 and phone MUST be in the same local network/wifi.