If you're replacing wood with wood, have you considered refinishing what you have?

With the limited information available in the two photographs (I would prefer to see the floor plan for the entire area you are planning to replace), I can't give you an answer.

Also, you may hear from some of the professionals about the wisdom of laying engineered wood over wood.

And if you have a LVP product on the main floor, you will definitely hear about the wisdom of laying wood over "plastic".