There is only one way to interpret "all".firepanda said:Corocoro could easily be overstating how many legendaries are accessible.
Actually, I think the article said something along the lines of being able to catch all the Legendaries if you have X, Y, OR and AS. So I don't think Yveltal, Xerneas and Zygarde will be in ORAS for example and that there will be version exclusives among the others. For example Lugia, Palkia, Darkrai and Zekrom in one game and Ho-Oh, Dialga, Cresselia and Reshiram in the other.
Yes, we know it's between all four games... so XY took care of gens 1/6, leaving gens 2-5 for ORAS (and yes probably spread over the two) unless they do patch XY to include some of these as Silktree suggested
(and I'm gonna ignore some people's comments about BW2 from now on, it is not a third version and it is a proof we can't always predict what would happen based on the past, cause no one saw that coming)