as long as you're above the emulator threshold, run using whatever you want

Swiss should be fine yes

ebay is usually fine for GBA and link cable, capture card there's a bunch of different options but a good relatively cheap one is a gv-usb2. but also I would recommend trying out some runs before you get these things to see if you actually enjoy the game, especially the GBA and link cable because they can be quite expensive and are basically useless outside of running the game

yeah, you can use whatever controller you want, it's fine

doing the trick is the best way to practice the timing

my opinion: the leaderboards are there to make a place for fair competition. it has been decided, by most speedrunners in general, that playing the game using official hardware is the way to go. so that is what we keep track of on the leaderboard. the leaderboard is not there to create a place for everyone to submit their runs. if you run on emulator, you are not playing in a way that is fair when comparing to everyone else, and so you're not gonna be on the same board. if you want to run on emulator, just don't submit your runs. yes, we could create emulator categories, sure, but I assure you they would not be active at all and would completely clog up the leaderboards. if loads of people want it, it's a thing that can be discussed, but we are not going to automatically do it just because other communities have decided to do it. it is by no means an obvious step in the right direction, there are many drawbacks as I have mentioned and other people have mentioned, and in my opinion they far outweigh the benefits imo speedrunning needs to move away from caring about the leaderboard so much, just run the game however you want, the leaderboard just represents and keeps track of the way that most people run a game

all that being said, I want to just say that this isn't me being a dictator mod or anything, I just wanted to share my opinion. there is always the option to discuss and make changes, but right now there is not really any want for it from the community