The main issue is rng. Everything is available in Legends Arceus, but distortions kinda ruin it. I had to wait on like 5 distortions before I got a porygon. Such a huge amount of time just sitting in-game doing nothing and waiting for the game to say "okay, now you can have it lol". Likewise for the link cables mori needed. Yes, you can consistently grind satchels to get them, but it takes far too many. There's virtually no effort required to travel anywhere in the game, especially once you have Braviary, so just travelling to points on a map to farm a currency is pretty dull. And then the alternative is waiting an undeterminate amount of time. Thankfully the majority of these pokemon can be obtained in the field anyway, so you don't need that many of those items. I don't think you can get some of them via side-quests though, or even as drops from pokemon.
Memento Mori wrote:Wild alpha steelix found! This is going very well, think I'd only have to grind satchels for either weavile or magmortar if I don't get lucky in a distortion.
You can get magmarizers from the special salesman guy by your house. But again, whether he offers it to you is rng, so just keep checking I guess.