Apple has recently released an update to their MacBook range which includes a brand new processor.
At the moment, this new processor causes an issue with Sketch plugins which is currently being looked at by the Sketch team. You can track the issue here https://github.com/skpm/sketch-module-web-view/issues/168
Unfortunately, that means that Marvel for Sketch on the new Apple silicon MacBooks is currently affected.
The solution for the moment is to Apple Rosetta, which enables a Mac with Apple silicon to use apps built for a Mac with an Intel processor.
You can find out how to install and use Rosetta here: