Even Real Madrid is choosing alternative options for Mbappe and they want to hire Jamal Musiala.
Jamal Musiala is a young player and he is currently under contract with Bayern Munich and he asked his team to extend his contract and increase his salary.
However, Manchester City also want to hire Musiala.
I believe Real Madrid still put Mbappe in their target list, but they are reluctant to pay the amount of money that PSG demand, because Madrid are desperate for a new world class striker as the replacement for Benzema. PSG use this Madrid's desperation to get the fee as high as possible, PSG also know that they need to sell Mbappe soon before he become free agent that makes PSG experience a big loss of money.
I dont think musiala can be an alternative option over mbappe because they have different profile between them.