Hello,
Unfortunately no. Although Blockly's codebase is split into multiple files, each file is not wrapped into an ES6 module or a closure module for that matter. The Blockly playground is currently the only way to truly run Blockly uncompressed.
However, we have recently started publishing sources and sourcemaps to our
package on npm. If you use something like webpack, you're able to configure it to extract these sourcemaps which should go a long way in helping you debug your code.
You can see how we've done this for our Blockly plugins script
here.
Cheers,
Sam