Change language of an Office 2016 Pro version

I have an installation of Office 2016 Pro in English and I want to change language to Spanish. The issue here is that the key I use does not work if I install same version in Spanish but it works in the English version. That is why I want to change it using the English version ISO installer. I would provide Anydesk access so you can make the change only when you test before on your PC. I will privide link of ISO I used as an installer. You can check pdf file uploaded. Thanks for reading this far.