Whatever relevant pitch was greenlit in 2019 is what the XCDE team would be working on next/now, they don't wait till a project's finished to make pitches, gotta have something lined up to go perhaps even while another dev cycle's ongoing.
now you're telling me things I've posted myself here
why do you even think a follow-up project was greenlit in 2019. they pitched XenoDE after Xenoblade 2 was done, alongside the Xenoblade 3 pitches. we're not living a world where we have
factual information (no guesswork or reading between the lines while hanging upside down from the ceiling) that a Xenoblade X port was ever
pitched and shot down.
What we know: almost exactly five years ago (
October 2018), Takahashi said putting Xenoblade X on Switch would sure cost a lot of money - this was when they had just shipped Torna and
started full production on XenobladeDE. The one where Takahashi says "
over the years" the only pitch that was accepted was Xenoblade was from
early Summer 2019 - note that this has been written into historic record solely via this one wordpress blogger's summarized translation (I'd be so happy if someone knows of an alternate full translation somewhere?). He's not even saying "oh we just pitched a bunch of new IP after Xenoblade 2 blew up and was a massive success and they said "no, just more Xenoblade, thanks!" The word "recently" is there, yes, but what does recently mean and mind you again that this a summarized translation, meaning it's not a good idea to hang onto every word literally.
These interviews are not a silver bullet to shut down hope/speculation of a new Xenoblade X version being in dev right now either since 2020 or since shipping Xenoblade 3/Future Redeemed. They conversely also don't tell us that they
are doing anything with Xenoblade X. All they tell us is that Takahashi thinks a Xenoblade X port would require lots of resources and that they've not pitched anything successfully outside of Xenoblades since Soma Bringer/Disaster came out.