There are 2 figures explaining transposed convolution. Which one is correct?

I have been struggling to understand transposed convolution. When I search for "transposed convolution", there are 2 figures explaining transposed convolution in which I think are not equivalent (or are they?).

Figure 1. Transposed Convolution as explained here

Figure 2. Transposed Convolution as explained here

Additionally, in Stanford's CS231N, transposed convolution was explained as in the Figure 1 (here, slide 52). Meanwhile, another online lecture from TUM's DVL explained transposed convolution as in the Figure 2 (here).