I've been testing this for about 10h of gameplay, even posted some tentative settings a few posts back in this thread. So far my recommendation would be: don't bother. You have to push the console really far, to the point it gets too loud, power draw may or may not be too high for sustained usage (not sure about what the power rails on the Switch are rated for), and there will still be stutters and slow downs. IMO the best (or rather, least annoying) setup is having the console docked or on official charger, use ReverseNX to force handheld graphics and overclock from there.
If you really want the extra eye candy from docked mode graphics your best bet would likely be to set memory as high as you safely can (varies between Erista and Mariko models) and then push the CPU, but again, not recommended. Your console will get LOUD and I can't say anything with certainty regarding possible long term damage from heat and/or high power draw.