None whatsoever. I usually Animal Crossing and some other game (Slay the Princess, Emio or The Legend of Zelda Echoes of Wisdom) for 2 hours or so tops. I've updated to the 19.0.1 a week or so ago (I've skipped the update 19.0.0, though). While I'm not using any hardware monitoring app, if I go into hbmenu I can see the CPU temperature which is around 50°C shortly after quitting the game. I've also been playing Moving Out with my girlfriend with the Switch docked and the Switch was never too hot to the touch when I was to remove it from the dock after our play session. My Switch even has a PlayVital's protective case which might make it a bit hotter due to the heat possibly absorbed by the outer shell. Note that I'm also not doing any kind of overclocking/underclocking or similar. Just playing games and that's all. I've charged it 20 or so hours ago to the 100% and didn't touch it until now and it's on 98%. It's the unpatched Erista model if that's even relevant. So far I have a around 700 hours of playtime on the Switch (my rough estimate is around 70% docked, 30% handheld mode).
That's about all the info I can give you.
I will monitor the battery level and CPU temperature today to see if it'll behave any different than usual and report back.
