Blending an image from two sides?

[RTL]

(03-13-2021, 11:51 AM)rich2005 Wrote: Use a layer mask.  The sequence:
Open the small image as a layer Image -> Open as Layers over the background.
Apply a layer mask to the small image layer layer  Layer -> Mask -> Add Layer mask Choose the 'white' option.
Click in the layer mask icon in the layers dock  to make it active.
With a black FG and the fuzzy brush (hardness 25) paint out the edges to suit. (make a mistake ? switch to white FG and paint back in)

A 40 second demo of all that https://i.imgur.com/1gV65x3.mp4

I like you sir. 

Thanks!