Hydra 1.0.0 is deprecating ObjectConf and the corresponding config structure to a simpler one without the params node. This removes a level of nesting from command line and configs overrides.
Hydra plugins are configured using the same mechanism. This means that this change will effect how all plugins are configured and overridden. This is a breaking change for code overriding configs in such plugins, but luckily it's easy to fix.
As an example, a Sweeper plugin override will change as follows: