This might be kind of farfetched, but...
I wonder if Beatrice is a "blanket term" which is used to describe women who have had a huge effect on Kinzo's life, and that's why the portrait keeps changing. And maybe the first woman was the actual Beatrice, and he was really in love with her, so he started seeing other women as "Beatrice".
If we assume the portrait will change one more time in Volume 4 and then loop through again in the answer arcs, that means there are 4 different Beatrices, and the "gifts" might correspond to the impact each Beatrice has had on his life.
"One shall be, all the gold from the Golden Land. " Most likely a Beatrice who helped Kinzo and gave him the gold.
"One shall be, the resurrection of the souls of all the dead. " I'm not sure about this one. Maybe one who got him into black magic at first? Or perhaps it's the only woman to be able to promote her pawn to her dead queen in Chess against Kinzo!</EndBadChessPun>
"One shall be, even the resurrection of the lost love. " could be a Beatrice that Kinzo fell in love with.
"One shall be, to put the Witch to sleep for all time. " I have a couple of thoughts on this one, but mostly thinking this is Kinzo's wife, which might be completely illogical due to things previously said. Or perhaps it's a woman who "hasn't happened yet"(lack of better term) and is the one who will stop Kinzo's obsession with Beatrice.
Like I said, it's a bit farout, but I thought it was interesting
I'm going to see if I can link this to the riddle at the beginning of the inscription.