St. Faustina wrote that she saw Jesus with his wounds. Also that she was disappointed with the original painting to the point where she cried. However, one would have assumed she would have told the artist to paint the wounds.
I referred to this video which shows and discusses the original Kazimirowski/ Vilnius image:
The original image appears to have had some indication of the wounds on his hands. If you look at the damaged pre-restoration image at 3:21 in the video, there is a dark mark on his upraised hand that may well be a depiction of a wound. At 1:38, Archbishop Salvatore Fisichella from the Vatican appears to confirm that this is indeed a depictioo of a hand wound.
The other hand is peeled at 3:21 so it’s harder to see. However, viewing the restored image at 1:39 it appears that there is a pink contrasting mark on the back of Jesus’ hand that might be a hand wound.
Of course the wound on his body is covered by his robe. The wounds on his feet also might be covered by his robe as only part of his feet are visible.
At 2:47 the video discusses the first restoration of the painting by a local artist, and that she used the same colors to paint herself a copy of the painting. Her copy (which isn’t that great of a copy admittedly - Jesus’ face looks quite different) shows a prominent wound on Jesus’ upraised hand. Despite her apparent lack of painting skills compared to the original artist, I would think an artist painting a copy would not include a wound if it wasn’t in the original.
I am inclined to think that at least the upraised hand does show a wound, even if it’s subtle. I understand the image was portraying the Risen Christ, so presumably he had wounds that Thomas could put his hand into, but Risen Jesus would not have been going around bleeding and needing to put bandages on those wounds, so it’s quite possible the wounds were very subtle and that the artist painted them as St. Faustina described them rather than as big red marks.