It is not a problem to replace headers, referrer, unique un, cookies.
What is a problem is to track the list of redirections, modification of cookies in the process of redirections, especially if there are many js on the site or God forbid more complicated technologies / dozens of requests and it is necessary to understand each
Using the Firefox debugger, it is possible to check transmitted cookies, the necessary headers may be too labor-intensive.
What are the means to analyze the chain of requests to obtain the final result, ideally generating the code themselves, or greatly facilitating the generation of code in php? Browser plug-ins come to mind, but I don’t know these