It’s fairly easy to blend two images in GIMP. All you have to do is: Open the two Images in GIMP. Blend the images using layer opacity/blend mode/layer mask. Export the resultant image as JPEG/PNG.

GIMP 3.0 finally dropped after years in the making, and honestly, it’s great. I have it installed and use it quite a bit. I was particularly excited to see the fresh GTK revamp and smoother UI tweaks.