Both. Lol. I was kind of excited to do so because of the whole version exclusive gym leader gimmick and for being the first and maybe only games that I got on launch. I also predicted they could possibly be my most nuzlocked games which so far might be the case.
Shield because of Galarian Ponyta/Rapidash. It really broke the pattern for me, as every other generation I had always defaulted to the "first" of the pair (Red, Gold, Ruby, Diamond, etc.). Galarian Ponyta/Rapidash was that important to me. Even though I also love Zacian and am sad I have never been able to get it.