Randomly I found the following tombs of russian people, immigrated to Luxembourg ,Grand-Duchy/Europe on the cemetery in Mertert. Different words and names are written in cyrillic but unfortunately I am unable to read .Some of these russian families and/or family members emigrated again to Paraguay.
To the genealogist whichever would be interested in, here a list of what I could read.
Alexander Gemarin 15.6.1886 – 14.3.1937 ( Tzaritzin ?)
Joh. Moldawsky 31.5.1894-7.3.1932
Nicolai Sokolow 9.8.1886- 22.11.1941
Blinoff Capiton 1878-1936 Eugénie Birukoff Lomteva/o/itc3.2.1908-
Pouchkarchko André 1897-1942 18.6.1957
Makarenko Simeon 1898-1944
General Polsikoff 26.10.1875-16.6.1938
Martinoff Timothee 1897-19.10.1929
Colonel Kermanow 3.5.1881-19.11.1959
Dimitri Lomtew 14.5.1882 16.11.1951
Colonel Koroeff 8.7.1884 Odessa? OAECCA
Marina Birukow 31.3.1940- 23.11.1941 - 15.12.1946 Mertert
Alexis Bonda sous lieutenant de l armée impériale
Colonel Poukh armée impériale1.10.1889/ 16.6.1958
12.2.1894 Kharkow – 3.6.1981 Luxembourg
Grizaenko Wladimir 20.12.1902-24.8.1946
Mouravieff Grégoire 7.12.1897-6.11.1969
Cathérine Mouravieff née Ivanoff 1898-1976
Kochouroff Valentin 15.2.1881-13.3.1943 and his spouse Eskoff Marie 1.8.1882-26.7.1970
Koursk - Mertert
Eskoff Marie 25.2.1858 – 26.9.1944
Nicolas Kagelmacher Koursk 27.11.1899 Wiltz
15.8.1983
Eben Jakob 1869-1948
One grave:1888-1948 1906-1950 1928-1951Begma-Troiitzkaja/Alexander Begma1899/1993
Wladimir Litvinsky 12.3.1900- 23.8.1950 Filtzoff Jow 19.5.1894-8.11.1956
Kozma Mokhoff –Kalatsch/Don 14.7.1886 -11.4.1970 Remich
One grave: Ouchakoff Ryndin /Larissa Ryndin St Peterburg/Poltawa *? + 8.11.1961
Serge Nagornoff /Antonina Anissimoff 3.9.1895-12.11.1954 – 26.2.1898-28.7.1981
Tretschin,(or Treschtine) archiprêtre, Russie 20.4.1879- 14.1.1966 Mersch
Pelagie Popoff 17.9.1885- 22.10.1965
Olga Serebriacoff 1902-1992 Marie Popova 1922-
Jean Serebriacoff 1895-1969
And I have an additional information ;I discovered in an newspaper article: there was a lady Maria Solovieff and her son Eugéne, he was born 28.1.1929 in Mertert, the first child born here by a russian woman, he died 19.11.2000. There is a picture of her and the baby and a picture of the priest Eugène Tretschin,too.
Apparently some of these russian families or family members emigrated from Luxembourg to Paraguay