They didnt officially announce the actual game though.
I dont remember "Pokemon 2019" to be officially announced as an actual title, until they do - its just heresay lol.
When you type in Pokemon 2019 - Detective Pikachu and the new Mewtwo movie show up in the results.
If it was actually announced, it would be #2 on my list.
A Pokemon mainline game was announced at the same time that Pokemon Let's Go was announced. Pokemon 19 has been a placeholder title I've been using since we don't have an official name for it yet. The game was confirmed to come out this year but nothing else was revealed. But since it was mentioned in a Nintendo Direct, I still count it.