The developer Felix Schwarz has now released a Public Beta, which also runs on macOS 10.15 Catalina.
Due to the new security measures Apple has introduced with Catalina, it is a bit more complex for you to set the appropriate rights for a remote control software during installation. But the Remote Buddy developer has found a clever solution: there is a settings window in which all relevant information and options are summarized. Very practical.
FLIRC IR Receiver and Amazon Remote on Mac
Also new: if you have a Mac without an infrared port, which affects pretty much all Macs from about 2012 onwards, you can simply get an infrared dongle from FLIRC. It is now perfectly supported by Remote Buddy. There is also support for new remotes like Amazon Remotes and Windows MCE Remotes.
The price for the final version is not fixed yet. Buyers of the previous version from 2018 and 2019 can upgrade for free. If the app was bought before, some financial support is necessary again.