Yes, Freda on Windows can load ebooks directly from the filesystem, either primary (read: C
storage or the expansion (read: D
storage, the latter typically being an SD or microSD card on Windows tablets.
I regularly use Freda on my 8" Windows tablet. I use calibre to manage my library, which is stored on my microSD card. I export (read: Save to Disk) from calibre to a folder, which is also on the microSD card, to create a small set of "current reads". These are then imported into Freda for reading and deleted when read. This has worked quite well for several years.