What’s the best way to manage a lot of 301 redirects in WordPress?

This is not really a clear question, and plugin suggestions are usually closed, as per the FAQ https://wordpress.stackexchange.com/faq

It all depends on what kind of work you want to do: either edit .htaccess or work with a plugin GUI.

Redirection works well and will allow entry of rules via CSV file and logging of all redirects as well as 404’s.

With Redirection, you sacrifice a amount of site performance, but it may be worth it to you.