I voted for Town. Either Pokemon or that will launch this year, and the other one next year. I don't think they will wait to launch Pokemon, especially if they are using assets/engine from Let's Go. However, if they feel Animal Crossing is going to be megaton then they could possibly wait, unless AC launches earlier in the year by a few months. Overall, I think Town will be the most likely pushed back.
But yes, I agree this year is almost too stacked, especially considering the Switch keeps getting more and more indie gems as well as the 10,000,000 Final Fantasy games that will be launching on it this year. I think, after this 2019 year is said and done, my backlog will be far larger than it is currently, despite my best efforts to play and beat games.