Not sure if this is an implementation issue or a documentation issue (I couldn't find any thing of the latter and I'm not fluent enough in python to find the former yet), but it seems like federated tracing is missing as part of the federated support. I checked the subgraph compatibility and it is missing from there as well (annotated as FTV1).

Note that it is different from the traditional apollo tracing: https://www.apollographql.com/docs/federation/metrics/#how-tracing-data-is-exposed-from-a-subgraph