Our most intriguing tea set cup and saucer....old, beautiful but of indeterminate origin

This is probably the cup with more back stamps, figures and numbers we have, but I could not find anything similar and I would be any idea you can suggest about its place of production. I was not cheap, we bought it several years ago…. Probably in August 2017 to Mauricio Adari in Rafaela Argentina. It is a city where there has been mostly immigrants from East Europe so it could had been from some country of what is now Belgium, Ukrania or Russia. Please open the pictures to appreciate correctly the details.
The style is in the manner of Russian cups….. with so much decorative features done with different techniques; mainly a mechanical decor over a background sprayed with an airbrush in tones of light gray and lavender, a drawing applied with a stamp using a stencil, decal - a multi-color print imitating hand-painted, extremely fashionable since the last quarter of the 19th century in Europe. Often the mechanical decor was added by hand, and this combination brought a special lightness and brightness to the drawing. In fact in this case you can see the decals with flowers in light blue an purple and others with the Cherubs groups and over the decals the stamp in dark purple mainly leaves and small flowers painted inside the lines with hand made brushes and over all this the gold lines. Also some of the little flowers are "jeweled" with the pearled relieves and there are some glossy enamel over everything that makes difficult the pictures with flash.
On the other hand the blank is not plane, the saucer and cup have a complex pattern like a drapery, and the hand of the cup is twisted..... The porcelain is hard paste of high quality but there are signs that it has been produced fired in wood oven....
Now the marks.... incised an F or E inside circle probably since the incised numbers had cancelled part of this mark, there are a double L in red, that has been delineated or stamped and colored inside by hand, and several numbers in red int the cup and in green in the saucer.
Please again I appreciate any comment.