May be it is interesting, the sculptor of the monument in Lemetti was Leo Lankinen, who was an Ingermanland Finn, moved from Northern Ingria during 1930-s and later (after Stalin's death) lived in Eastern Karelia. He identified himself as Finn and spoke Finnish. It is a chapter about this monument in a book about Leo Lankinen. Unfortunately the sculptor died some time before the official opening of the monument.
This is very interesting. I found a chronology of monument design.
July 1992 - Moscow government discussed the idea about memorial to fallen soldiers in Pitkaranta. Initiator of idea was veteran of WWII S.M. Tikhomirov. Moscow government gave 10.000.000 roubles for this.
August 1992 - Pitkaranta town council discussed the agreement between Russia and Finland from 11.07.1992 to perpetuate the memory of Soviet and Finnish soldiers, fallen during WWII. It was decided to open monument in Pitkaranta and collect money for it.
28 August 1993 - memorial board in Pitkaranta "To the memory of fallen in 1940" was installed from citizen community of Rantasalmi.
01 February 1994 - competition for the design of memorial. Participants - 4 Karelian, 6 Moscow, 1 Petersburg, 3 Finnish sculptors. The 1st place was given to the "Cross of Sorrow" by Leo Lankinen from Karelia, 2nd place - to B. Plenkin from St. Petersburg, 3rd place - V. Bykov from Moscow. The planned cost should be 85000 $.
23 February 1994 - decree of Russian government No.244 about financing of monument.
1994 - monument in Suomussalmi (Finland) was installed. Designer - Russian sculptor Oleg Komov.
February 1995 - Karelian government established commitee for supervising and coordination the construction of monument "Cross of Sorrow"
May 1995 - Russian sculptor E. Akulov started the design of monument model together with L. Lankinen. Russian ministry of culture sent to Karelia 200.000.000 roubles for monument construction.
May 1996 - 1:1 model was finished [height 5.25 m]
December 1996 - Control Department of Russian President reported that Karelian government received 377.000.000 roubles for monument [including private donations from Soviet and Finnish war veterans]
17.12.1996 - Karelian sculptor Leo Lankinen [academician of Soviet Academy of Arts] died. He was very against any differentiations between Finland and Russia during the design of his monument, and when he was asked which mother on the cross will be Finnish and which will be Soviet/Russian, he answered: "Doesn't matter. They should be sisters and mothers of fallen soldiers". Finn Leo Lankinen was one of the best Karelian sculptors, who felt the national characters of Finns and Karelians extremelly subtly [and made a lot of sculptures of famous Finns, Karelians and Russians who lived in Karelia] and he was free from Soviet "heroic" style of art.
December 1997 - sculptor E. Akulov completelly finished the model of monument in plaster cast.
26.01.1998 - experts from Russian ministry of culture recommended to cast the monument from cast iron instead of stainless steel.
March 1998 - governments of Karelia and Russia spent 334.116.000 roubles for monument, many works were performed free of charge.
31.08.1999 - factory "Petrozavodskmash" began to cast the monument. The original plaster cast model was presented to Finnish town Kuopio. The book "Memory and sorrow" was published - memoires of soldiers, participated in combats in Lemetti and Soviet-Finnish (Winter) war in general.
23.01.2000 - administration of Finnish town Kuopio gave 100.000 markkaa [10% from the cost of the whole monument] as the donation.
26 April 2000 - the monument "Cross of Sorrow" was installed at crossroad Suojärvi-Petrozavodsk. The majority of Karelian officials very support the idea of joint monument to Soviet and Finnish soldiers, but there were/are also some enemies of such monument to friendship between Russia and Finland who ask to make two separate monuments for fallen Soviet and Finnish soldiers or to install monument only to Soviet soldiers.
27 June 2000 - solemn ceremony of grand opening of the monument. Participants: government delegations from Finland, Russia, Karelia; official delegations from Moscow and St.Petersburg; official delegations from Petrozavodsk and Kuopio; members of Russian and Finnish societies of friendships between Russia and Finland; WWII veterans from different towns of Russian and Finland especially of the units participated in Lemetti combats; commanders of Karelian military units; historians, priests from both sides.
The monument was opened by four veterans - Valentin Khaletsky [Russia], Kallervo Savolainen [Finland], Ivan Averin [Russia], Mikko Laylyka [Finland]. Official speeches, concert where Russian and Finnish veterans sang songs including from the time of Winter war period, etc.
At the moment there is a tradition to put flowers to the monument if you reach the crossroads at Lemetti.
P.S. In German journals I found two short descriptions of the memorial - "to Soviet and Finnish soldiers who killed each other here during two wars in 1939-1940 and 1941-1944" and "to Soviet and Finnish war heroes fallen at this place during WWII". I like the second name much more, but this is my personal opinion.
Photo from http://heninen.net/kollaa/kuvia/004.jpg
Reenactment near Lemetti, 2002 - the war came to end