Virtuos is handling the ports of Final Fantasy X | X-2 HD Remaster and Final Fantasy XII: The Zodiac Age to Switch. They've certainly handled their fair share of Switch ports, but taking on Final Fantasy is of a higher caliber. In an interview with Nintendo Life, Virtuous discusses their time bringing the games over to Switch.
I would say it was quite technically challenging because to make Final Fantasy work on Switch, we needed to convert it to 64GB. So, the Switch version needed to be shrunk without impacting the performance. As this requires a fair amount of skill, we have a small team specifically to target these parts of the remaster.