How can I picture an unfolded RNN as a normal Feed Forward Network?
I cannot be sure whether this graphical representation is fully correct or wrong, but your misunderstanding looks like it revolves around what is an LSTM cell and LSTM neurons.
In the second figure, the nodes depicted should be LSTM cells. A cell is in essence a forward neural network consisting of neurons and so an analytic representation of it may look like what the first figure shows, although admittedly it looks very confusing.
See a recent discussion on that exact matter here What is the difference between a &quot;cell&quot; and a &quot;layer&quot; within neural networks?.