MAYFLASH Magic-NS is what I use to hook my ASP to the Switch. Also works for hooking up a Wii Fighting Stick to the ASP.
Would a wireless controller adapter work instead? I thought the ALP supported Bluetooth with BYOG, you may be able to have that connect to something like this Mayflash. It may also work with normal OTG wired as well.
https://smile.amazon.com/Mayflash-Magic-NS-Wireless-Controller-Nintendo/dp/B079B5KHWQ
thanks! I purchased this one instead and I'll return the 8bitdo one. hope this works :-)
https://www.amazon.com/gp/product/B079B5KHWQ/ref=ppx\_yo\_dt\_b\_asin\_title\_o00\_s00?ie=UTF8&psc=1
https://www.amazon.com/dp/B079B5KHWQ/ref=cm_sw_r_cp_apa_i_3z17CbE3G976Q
I have one of these and use it on multiple consoles including the classic. Works flawlessly.
Lots of people have problems with the 8bitdo one. The Mayflash MagicNS works better.
https://www.amazon.com/Mayflash-Magic-NS-Wireless-Controller-Nintendo/dp/B079B5KHWQ
the best wired pads aren't for swtich, An XBOX one/Series Razer Wolverine v2 is my wired pad of choice
Get the Mayflash adapter and update it then get this
This is the adapter to get
As far as USB-A to USB-C adapters any should work. Otherwise, if you can't map your guitar buttons you may need this
https://www.amazon.com/dp/B079B5KHWQ?psc=1&ref=ppx\_yo2ov\_dt\_b\_product\_details
https://www.amazon.com/Wireless-Bluetooth-Adapter-Nintendo-Switch-Raspberry/dp/B0786JC6VW
https://www.amazon.com/Mayflash-Magic-NS-Wireless-Controller-Nintendo/dp/B079B5KHWQ
Here's example of the dongle I mentioned. It let you connect famous controller like DS4/XBox One to switch. These dongle do not let you communicate with PC directly. Well it is not really DIY but I figured it should be easier to find XInput/XBox signal reference than directly involve with Joy Con. So either reverse engineer the signal send to adapter or reverse engineer the adapter driver itself then connect to PC directly. (not even sure if the hardware let you do that lol)