How to batch replace the double-backslash \\ in a field with a usable character?

[ohrenkino]

See e.g. this thread:

Replacing Double-back-slash With Semi-colon-Space

Sorry if this is explained elsewhere. I could not find it. Tags like Composer and Style have up to several values (e.g. Michael Preston Barr\\Dion McGregor or World Fusion\\Latin Jazz\\Afro-Cuban\\Afro-Cuban Jazz\\Cuban Traditions) MP3tag only displays the first value in the list and I do not see the rest of the values. I wish to convert from \\ to ; (semi-colon followed by a space) as a list separator. MP3tag displays all the values when saved like Michael Preston Barr; Dion McGregor or …

or use the search function and "double backslash" as search words.