Roadmap for compatibility with other Corona apps?

Since there are many Corona apps in many countries currently being developed and pretty much all rely on the Google/Apple contact tracing framework, what is the roadmap for collaboration with these other countries? Is it planned that these different apps are compatible?
I mean due to border-less Europe this would make pretty much sense.

Review the issue's question about compatibility between Corona apps using the Google/Apple contact tracing framework. Start by checking the project's current roadmap and any existing collaboration plans; done would require an agreed, documented compatibility roadmap, but the issue provides no files, tests, or implementation entry point.

Written by the indexing model from the issue text.