Defer not working with schema stitching

[ramiel]

I'm trying to use @defer and I get the following behaviour: the query result is returned like there's no defer (so as slow as the slowest field).

I have a reproduction here: https://codesandbox.io/p/devbox/tender-pine-lcmrx2?workspaceId=ws_ApAxKFyKo3qesh2PbPDdwc

Note that defer (provided by @graphql-yoga/plugin-defer-stream) is not working with two local schemas, so not even through a http executor.