Masked redirect of the subdirectory home page (only home!)

Two subdirectories (different wordpress installations) share the same database and the same prefix, in order to share the same posts. The only problem is that I do not want the home subdirectories to be the same for both, or rather I wish they had title, text, meta description and meta title different. To achieve this I need every home, but only the home and not all the sudirectories, to have a redirect masked to a different page, but I'm available to evaluate another solution that respects the purpose mentioned above. Sites are ready for your work, I can provide wordpress and ftp credentials when you want. /subfolderA/ >>>masked redirect to>>> /subfolderA/home-a/ /subfolderB/ >>>masked redirect to>>> /subfolderB/home-b/ /subfolderA/post/ >>must remain>> /subfolderA/post/ /subfolderB/post/ >>must remain>> /subfolderB/post/