Since the War in Donbass, emerged for Russia a problem with sanctions to foreign contries. It has been a problem of limited impact for Russia, because the country always has been working its defense industry, leaving little room to dependence of foreign imports.
In the refered to the Russian Navy, there is some impact on components (like engines,...), that Russia is working to eliminate, but only a few complete ships are of foreign origin, and all are auxiliary ships, not combat ships. Obviously the position of these ships of foreign origin is under question. Likely these ships will be out of the Russian Navy in the short term, but the question is what to do with them? Also we can give an opinion here, using one of the tools of this forum, the polls.
It is necessary to note what is considered a foreign ship. Ships of Sovietic/Russian design are not considered foreign ships, despite to be built sometimes outside of Russia or even out of the Soviet Union, in countries that were in good terms with Russia and the Soviet Union at the time.
In the other side, foreign designs are considered foreign ships, because it would be more problem for repairs and to have spare parts, even in the case of partial production in Russia or the Soviet Union.
Also it is necessary to note that shipborne boats and midget submarines are not considered independent ships, are considered components of a bigger unit. If they are of foreign origin, they are treated as foreign components.
Taking it into account, the list of foreign ships in the Russian Navy is low today. 41 of the 1025 ships of the Russian Navy (including the 18 combat and auxiliary ships captured to Ukraine and the 13 combat ships of the Russian Coast Guard). It means only a 4.00% of the total fleet of the Russian Navy.
Some reference with pictures of the foreign ships:
Dry-cargo ships purchased for the operation in Syria: 1985 Dvinitsa-50 http://fleetphoto.ru/ship/54458/
March 31, 2017
Dry-cargo ships purchased for the operation in Syria: 1985 Vologda-50 http://fleetphoto.ru/ship/54485/
April 12, 2017
Dry-cargo ships purchased for the operation in Syria: 1996 Kyzyl-60 http://fleetphoto.ru/ship/55363/
March 31, 2017
Dry-cargo ships purchased for the operation in Syria: 1987 Kazan-60 http://fleetphoto.ru/ship/16128/
March 31, 2017
Type Dora: 1941 Istra http://fleetphoto.ru/ship/6223/ (Captured to Germany in WWII)
October 12, 2017
Type PPEK-30: 19?? PK-16030 http://fleetphoto.ru/ship/10295/
March 25, 2013
Type PPEK-30: 1959 PK-103130 http://fleetphoto.ru/ship/40785/
January 20, 2017
Type Dubna: 1974 Dubna http://fleetphoto.ru/ship/68854/ http://www.marinetraffic.com/en/ais/details/ships/shipid:930618/mmsi:-7347471/imo:7347471/vessel:DUBNA
June 20, 2015
Type Dubna: 1975 Irkut http://fleetphoto.ru/ship/26060/
March 12, 2014
Type Dubna: 1979 Pechenga http://fleetphoto.ru/ship/6375/
March 22, 2016
Type Paltus: 1980 PK-1150 http://fleetphoto.ru/ship/45784/
November 27, 2014
Project REF-675: 1982 Kama http://fleetphoto.ru/ship/12009/
May 13, 2016 (black ship in the center)
Project REF-675: 1982 Vyazma http://fleetphoto.ru/ship/42747/
October 23, 2015
Project D-9030: 1976 PK-119025 http://fleetphoto.ru/ship/4926/
September 14, 2015
Project D-9021: 198? PK-33016 http://fleetphoto.ru/ship/34964/
June 10, 2018 (floating crane after the ship)
Project SK620: 1978 Belomorets http://fleetphoto.ru/ship/6308/
June 1, 2017
Project SK620: 1980 PSK-405 http://fleetphoto.ru/ship/10392/
December 22, 2016
Project SK620: 19?? PSK-2017 http://fleetphoto.ru/ship/34799/
November 13, 2011
Project SK620: 19?? PSK-1304 http://fleetphoto.ru/ship/44610/
July 30, 2017
Project SK620: 1983 EK-1412 http://fleetphoto.ru/ship/42817/
July 27, 2017
Project SK620: 1985 PSK-1562 http://fleetphoto.ru/ship/56311/
July 12, 2017
Project SK620: 19?? PSK-1556 http://fleetphoto.ru/ship/60223/
April 23, 2016
Project SK620: 19?? PSK-302 http://fleetphoto.ru/ship/73679/
July 30, 2017
Project REF-100: 1985 GS-525 http://fleetphoto.ru/ship/41469/
February 17, 2017
Project REF-100: 1985 GS-526 http://fleetphoto.ru/ship/46939/
April 4, 2015
Project N3291: 1988 RB-346 http://fleetphoto.ru/ship/1398/
October 4, 2017
Project N3291: 1988 RB-347 http://fleetphoto.ru/ship/2053/
August 15, 2009
Project N3291: 1988 RB-348 http://fleetphoto.ru/ship/1631/
May 27, 2017
Project R-5757: 1989 Nikolay Chiker http://fleetphoto.ru/ship/29166/
September 18,2015
Project R-5757: 1989 Fotiy Krylov http://fleetphoto.ru/ship/39062/
March 17, 2016
Project UK-3: 1982 UK-115 http://fleetphoto.ru/ship/10829/
July 26,2015
Project UK-3: 19?? UK-162 http://fleetphoto.ru/ship/10827/
March 5, 2015
Project UK-3: 1983 UK-712 http://fleetphoto.ru/ship/6464/
June 6, 2010 (ship 229)
Project UK-3: 1990 UK-164 http://fleetphoto.ru/ship/38120/
October 18, 2013 (ship 164)
Project UK-3: 19?? UK-288 http://fleetphoto.ru/ship/38121/
October 18, 2013 (ship 288)
Project V92: 1983 Evgenij Gorigledzhan http://fleetphoto.ru/ship/59302/ (Modified in 2016 to a Project 02670 ship)
2016 or 2017
Project V92: 1990 Kalar http://fleetphoto.ru/ship/24461/
March 14, 2016
Project D-9040 V-02: 1989 PK-128035 http://fleetphoto.ru/ship/47028/
May 10, 2016
Project V-820: 19?? RB-33 http://fleetphoto.ru/ship/26210/
June 22, 2017
Type IC16MII: 2011 P-834 http://fleetphoto.ru/ship/42778/
May 15, 2017
Type IC16MII: 2011 P-835 http://fleetphoto.ru/ship/42785/
October 19, 2016
With the problems with foreign material and spare parts, it seems logical that Russia want not to keep these ships in the Armed Forces. An exit would be logical, and taking into account the difference on age and state of the ships, different solutions for them are likely.
In the case of the newest ships and the ships in better condition, an option would be to transfer them to non-military agencies of the gouvernment, that can be related with security issues, but without being part of the Russian Armed Forces. Surely, without being the alone option, the most obvious case would be the Russian Coast Guard, that has itself hundreds of ships of different size and role.
Also there are options that mean to keep not some ships. it would be possible a sale of some ship to some buyer, local or foreign, or even a transfer as aid to some foreign ally. In the case of the oldest ships and the ships in worst condition, a likely option would be decommission and scrapping process.
What would you do? (Interesting to check the photographies in the link to every ship).