I have a question building off of this. I think it belongs here because of its relation to what OP is asking, but I understand if it gets removed as a non-answer to their question
If Marx and Engels imagine an economy based on labor-time, how do they address the following potential issues:
Labor-time inflation due to greater technology. As machines become better, we can produce things faster, and work for a shorter period of time. How does this factor in to the labor value put into a good?
How do you normalize labor-time across industries? People doing different tasks will spend different amounts of time, and some labor is front-loaded with education/training. For example, a doctor spends years training to be a doctor and a miner can learn to do their job in a few weeks. How do you address their sunk labor when valuing labor-time?