Use Microsoft Edge not Chrome.
Go to Microsoft website.
Look for products; ignore Microsoft 365.
FIND ADDITIONAL PRODUCTS ALONGSIDE oFFICE MAIN PRODUCTS.
Use drop-down to get to Visio rather than Project.
Select the right internal tab (Visio Professional, 2019 within the dates listed)
Go to Microsoft Setup within the internal tab
Where it says to enter the product code, do that
Then click the download button. You should get an image file (.img)
Move the image file to desktop.
Run the image file (this gives access to files within it)
A new drive lketter should now be mounted - I saw "DVD Drive (G:) 16.0.14026.20302"
Run Setup.exe from within the mounted image
Switch to 64-bit not 32-bit if necessary to match the installed Office Pro 2019
Enter the product key when prompted.
The installer eventually completed. Visio was now installed and the other Office products had not been removed!!
Go into Visio, open a drawing or start to create a new one.
Enter the product key to activate when prompted.
All done!!