I was writing a simple test with sprites that uses NMI. Well in FCEU and Nintendulator the sprites are displayed as a single dot of color 0 at x and y position in OAM.
You're probably doing something wrong with $2000.3 that setups the sprite pattern table, or with the sprite tile index.
Sorry, that was color 1, not 0.
That can't be, cuz I used only one pattern table.