I just implemented xBR for two of my patches (Peixoto's patches for a few old games)

eventually (this year, i hope): my patches will become something like DXWnd, so you will be able to use the filter (and other filters) in other games

DxWnd does support hq4x, expect low framerates with it though. ReShade can do a hq4x-like post-process filter (should work with DgVoodoo and DXGL).