Best way to merge from another git repository -

Hi guys, I want to hear your opinion. I have a situation in which we have recently moved to GIT, after migration and after some development work, we saw that the migration had gone wrong. We have made a new repository again.

The problem here is the hash that is different between the repositories.

I want to merge only our development works with the full development history from the present master. What branch should I take the best option in the new repository? If I add two remote and merge then GIT creates a completely new command patch? Cherry pick?