How to get Image Overlay/Ghost Image in R6

[Nazgul]

Hi guys, I came across ML while trying to find a way to add a ghost image/overlay (Like Multiple exposure) for my videos to make better match cuts on my R6.

From what I have learnt so far is that there is no ML version yet for R6. Now I have two queries
1. I wanted to know does anyone has any suggestions as to how I can add ghost image/overlay till someone comes up with ML for R6.
2. When using Multiple Exposure, I am not able to use an image that I have extracted from my 4k footage (R6 lets you chose any frame in a video and make a jpeg of the same). For some reason this extracted jpeg doesn't show up when I try to use it in Multiple Exposure.