One of the things I like say about plot, on those occasions when I’ve been encouraged to pontificate about such matters, is that in my opinion plot is necessary but it’s not important — that it’s not the story, it’s just the ropes and pegs and tentpoles that make the story into a habitable space and not a flat puddle of metaphorical canvas. So you construct/adapt/appropriate whatever structure best holds up the material you’re working with.
I tend to think of plot mostly in terms of structure, anyway, rather than limiting it to the sort of interlocking-gears, wheels-within- wheels variety of highly constructed storytelling that a lot of people seem to think of when they say the word, “plot.” (The closest I’ve ever come to the latter is on the two or three occasions when I’ve committed mystery-based plots — mysteries really do have to be plotted backwards, not to mention from both ends toward the middle, and at some point in the proceedings each time I’ve found myself having to make one master list for what really happened and when, and a bunch of secondary lists for the various major characters, saying what each of them knew about what happened and when they knew it and what they thought had happened and when they thought it. There’s a reason I don’t do mysteries all that often . . . .)
You can structure a story around other things than action, though action’s the easiest for most people. Recurring images, cultural/folkloric motifs and archetypes, even shapes and diagrams — whatever works. And you don’t have to tell anyone what you’re using unless you want to; the graduate students of future generations have to get their jollies from somewhere.