If your 2K means the same as 1440p, then the mClassic is what you want. I really liked how it looked on my 1440p monitor before I 'upgraded' to 4K.
mClassic can upscale 480/720/1080p to 1440p at 60 Hz. 4K is more difficult, as you need another device to throttle the signal to 30 Hz (which is not necessarily a huge downgrade, as many Switch games only run at 30 FPS). And most 4K TVs do not report 1440p as a supported resolution (some may accept 1440p with an EDID emulator, but many won't show 1440p at all), so the mClassic will only go up to 1080p60 on them.