Is it possible to export a reagent component so that a JS project interprets it as a react component? :)

it is, but the problem is that your exported component is going to include most of clojurescript core, for example, so it's going to be quite big

at least shadow-cljs lets you make a build that creates a commonjs or es module

Check reactify-component. Shadow-cljs is indeed easiest tooling for this (https://shadow-cljs.github.io/docs/UsersGuide.html#target-node-library) but there are non-reagent related tradeoffs.

https://github.com/reagent-project/reagent/blob/master/CHANGELOG.md#110-2021-06-05