index.js

const Module = require('module');
const {isAbsolute} = require('path');
const {pathToFileURL} = require('url');

exports.dynamicImport = importEsm;
exports.importEsm = importEsm;

async function importEsm(specifier, module) {
    if(isAbsolute(specifier)) {
        return import(pathToFileURL(specifier).href);
    }
    let resolvedPath;
    try {
        const req = Module.createRequire(module.filename);
        try {
            resolvedPath = req.resolve(Path.posix.join(specifier, 'package.json'));
        } catch {
            resolvedPath = req.resolve(specifier);
        }
        resolvedPath = pathToFileURL(resolvedPath).href;
    } catch {
        throw new Error(`Unable to locate module "${specifier}" relative to "${module?.filename}" using the CommonJS resolver.  Consider passing an absolute path to the target module.`);
    }
    return import(resolvedPath);
}