I've been experimenting with the alexa lists sample code here
if you already have a custom list on your alexa it will show up in the list of lists when you are setting up this flow.
I have modified the flow to access the custom list and everything work with the exception of adding an item to the list via node red. Items added via alexa show up there but I get an error when trying to add an item to the custom list
2/8/2021, 6:52:40 AMnode: 1e3b9659.914dca
msg : string[35]
"expected a string 'list' and 'text'"
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