Supported devices

Bluetooth adapters

ASUS USB-BT400
https://www.amazon.com/dp/B00DJ83070

TP-Link USB Bluetooth Adapter
https://www.amazon.com/dp/B07V1SZCY6?ref=ppx_pop_mob_ap_share

USB Wi-Fi adapters

TP-Link USB Wi-Fi Adapter for PC N150
https://www.amazon.com/dp/B008IFXQFU

Realtek Mini USB Wireless 802.11B/G/N LAN Card RTL8188
Reported as working but only limited testing has been done

Bluetooth controllers

Switch pro controller
DualShock3
DualShock4
8bitdo most SHOULD work
8bitdo M30
8bitdo SF30 pro

Wired controllers

NES and SNES controllers will work on either system
USB controllers including PSC and Genesis/MegaDrive now work on SNES
PSC controller will work on Sega post mod
8bitdo most should work in wired mode
Old Sega Saturn USB controller (cypress)
*Retrobit genesis 6 button and Saturn controllers both work (need mapping?)
Retro Fighters BrawlerGen Genesis Mini Controller 6 button

OTG adapters

AuviPal 2-in-1 Micro USB to USB Adapter (OTG Cable + Power Cable) - 2 Pack
https://www.amazon.com/gp/product/B07FY9Z9GD?pldnSite=1

Yonisun Micro USB Host OTG Cable with USB Power for Samsung/HTC/Nexus/Lg Phones and Tablets
https://www.amazon.com/gp/product/B00JCZ2FQQ?pldnSite=1

OTG hubs

BoTian Micro USB OTG and Charging hub for Windows Tablet simultaneous Charging and Data transmisson 。Micro USB OTG hub for Android Tablet and Smart Phone Single Data
https://www.amazon.com/gp/product/B07XMBVQ2R?pldnSite=1

SUYAMA USB OTG Adapter for TV Stick, All-New TV (2017), Nintendo Classic Mini, Sony Playstation Classic - Micro USB HUB Adaptor with Power Supply
https://www.amazon.com/gp/product/B07VVNNQ8Q?pldnSite=1

Advanced - requires soldering
MakerSpot Micro USB OTG Hub can be used if you feel up to soldering a USB end onto it.

The small angled adapter is no longer recommended due to easily loses data connection at the slightest nudge.