Ability to use other plugin's transformers

Feature Use Case

If I have a transform that converts, say, MDX to TypeScript, what's the best way to have the resulting code pass through all the transforms TypeScript would go though according to the project config?

Feature Proposal

Right now I'm 'hacking' it by writing a resolver that appends .tsx to the resolved path, then a loader that loads the right file. That means the other transformers think the file ends in .tsx and do the right thing. But… it feels like there should be an easier way.

One way could be to allow a transform to return a new path value that would be used by subsequent transformers.

Another way would be to allow something like const result = await this.transform(value, path) that runs through all the transformers, similar to what this.resolve provides for resolving.

The issue names no files or tests; start by tracing the plugin transform and resolve hooks described in the proposal. Compare the proposed path-return and nested-transform approaches, then identify the intended API and tests needed to show that transformed output passes through the configured TypeScript transformers.