Brand new CC install on new Windows 10 install, new hard drive. Exporting via SFW.
I had copied over one custom setting file to ~\AppData\Roaming\Adobe\Adobe Photoshop CC 2019\Optimized Settings\ but it wasn't showing in the SFW Preset list.
Decided to create a new preset, and Photoshop offered to save it in the CC 2018 folder instead of CC 2019. Cancelled that and copied my old preset into CC 2018 and verified that it showed up in SFW.