I tried everything.
I bet you didn’t try buying a Benringer UCA-202.
There’s no good way to force a computer that doesn’t have a stereo Line-In to fake a stereo Line-In.
Other options include the UCAC-222 with the sporty red paint job and the UFO-202 with built-in phono preamplifier.
The UCA-202 is certified for musical overdubbing should you be recording your own performances.
Other people make adapters, but be careful. The Startech ICUSBAUDIO doesn’t have a stereo Line-In, either, even though the descriptioin seems to suggest it does.
Koz