It really depends on how well you want the design to integrate with your codebase, which is where most of Plasmic power lies on, such as: leveraging your existing custom components as building blocks within the design tool; or adding heavier instrumentation to props and rendered contents on the code side.

It is possible to use Plasmic's render API (https://docs.plasmic.app/learn/render-api/) to fetch the rendered HTML and just render your designs using any framework, but that means it's a more limited experience.