How to set scalacOptions for template and route compilation specifically?

I’d like to use -Ywarn-unused:imports and -Xfatal-warnings as scalacOption values for my project, but unfortunately they conflict with twirl template compilation and routes compilation, both of which have imports included in them I cannot control or adjust. So I’d like to disable the -Ywarn-unused:imports for the compilation of those, but I can’t manage to get it working. Is there a sbt key or scope like scalacOptions in compileTemplates -= "-Ywarn-unused:imports" that I can use?