Yes and no. A SATA SSD inside a USB 2.0 enclosure (with a Cypress chip) works, but you get zero speed benefit. The Wii caps out at ~30MB/s, while an SSD does 500MB/s. You are paying for speed the Wii cannot use.
These drives are statistically reported to fail with USB Loader GX: usb loader gx usb compatibility list
These drives have proven to fail regardless of formatting, Y-cables, or USB ports. The controller chips simply refuse to handshake with the Wii’s USB stack. Yes and no
To understand the value of this list, you must understand the Wii’s hardware flaw. The Wii has only two USB 2.0 ports, and the console is notoriously picky about power consumption and data protocols. The Compatibility List is designed to tell you
The Compatibility List is designed to tell you which specific drive models suffer from these fatal flaws and which ones work "plug-and-play."