Use Vash templates with Fractal.
See the Fractal view templates guide for details on customisation and usage.
In fractal.js put in:
const vash = require('@pentia/fractal-vash-adapter')({
helpersName: 'html'
});
fractal.components.engine(vash);
fractal.components.set('ext', '.cshtml');
And you should be good to go.