The Majora's Mask Resources Master Document contains useful technical information not found on ZSR as it only loosely pertains to learning speedruns. Many of the route documents on the Master Document are out of date, and several other links on it are redundant with information on ZSR.
Some of these videos focus on specific categories, but all of them include useful general information, tutorials, and examples:
These YouTube channels contain useful timing and strat videos: