The split between English and Japanese releases comes down to print quality, distribution, and market demand: English Releases: Feature natural yellow borders, standard booster pack pulls (often 1 in 2 boxes), highly variable factory cuts, and a massive grading population due to global collector demand
In total, there are 139 cards in Paldean Fates [PAF] that feature a Shiny Pokmon
This is a bit of a loaded question
Making the Top 8 of the World Championship is considered nearly impossible
It varies from card to card, but here are some of the factors that influence the value of Japanese Pokmon cards, as well as some examples of direct price comparisons
Tapping for three colors of mana is huge and not something a lot of lands are able to do