I think RetroArch runs the same core as Bizhawk so it should be fine. Emulators are not optimal for speedrunning, especially for N64 games as they are not accurate for most of them. Duck Dodgers seems to work fine on bizhawk core, similar to console.

Yes, as long as its an accepted emulator with correct settings. Use Project 64 1.6/1.7, or Bishawk

Done

You have to perform the trick in FF every time you want to do the run because that is how the trick works. The moves are transferred from the file you die in FFM in to the file where you next walk through a Grunty's Lair Loading Zone. The file Golderzoa would give you would only be the file where you would die in FF.

xbox360 version differences: Unable to Skip Text Faster Loading Zones Less Lag Harder to perform Flying Clips(But not impossible but very very hard) Able to Deathwarp in levels and keep notes

However because of all these differences xbox is about 3 minutes slower than n64.

PJ64 2 is banned for almost all speedruns since it is faster than normal. For Banjo, even Emulators are still not the best way to run the game, since they are not 100% accurate. If you want to run on emulator to start with that is fine, however i would recommend once if you get serious to make the switch as emulator is slower in terms of loading zones so you would lose around 1 minute, however the game has less lag making some movement sections faster.

The best emulators to run the game are PJ64 1.6 , PJ64 1.7 and Bishawk