The Switch version of SMB3 is now allowed for all 4 categories of Super Mario Bros. 3 (any%, any% no WW, any% warpless, 100%).
Note that the Switch has a framerate very slightly slower than the NES and you'll lose a few seconds over the course of a 100% run due to it (the difference is quite negligible unless you're going for the WR).
In the case of any%, note that the wrong warp setups possible on NES (that you can see all over the LB currently) are the standard we use to determine which version should be allowed or not. For example it was found out that WiiVC behaved differently in that regard and as a consequence was banned for this category.
What it means is that with the informations we gathered so far, it seems that the Switch behaves similarly to the NES, and NES setups have been found to work on the Switch. This however might be reassessed in the future if new data comes up, with Switch specific possibilities for example. If that were the case, the version might become banned for this category alone, but we would still grandfather in older runs using "NES compatible setups" so don't be worried.
All in all, if you're planning on playing any% on the Switch version and are noticing something in 7-1 that seems to differ from the NES, or a setup possibility that nobody else seems to use, please contact us (on Discord) and we'll look into it if necessary.