Tantric Texts is the impressive, near-complete 22 volume collection of tantric root texts compiled, edited and commented by Arthur Avalon (Sir John Woodroffe) from 1915 to 1953. The works have only been printed once in their complete form, by Agamanusandhana Samiti, Calcutta, and they are practically impossible to find in print. There is however a 4.000-page compilation with translations of the Sanskrit material available from Amazon. Find it here: https://amzn.to/2OgbgZT
Please consider that the works below are huge files, some larger than 120MB. Interesting for English readers are only the long introductions and comments on key tantric concepts, most of the works are printed in Sanskrit. We have a number of more readable books by Sir John Woodroffe here on the site, do a search
Language title : Tantric Texts 20 Chidgagana Chandrika – Swami Trivikrama Tirtha 1937