I ended up down a bit of a rabbit hole trying to get eslint-plugin-import-x working in VSCode. After raising un-ts/eslint-plugin-import-x#429 I was given a workaround un-ts/eslint-plugin-import-x#429 (comment).

That solves it for now, but from what I gather the problem is somewhere around here, or at least should be first apparent here. It would be really helpful if unrs-resover was a bit more verbose in what had gone wrong. See import-js/eslint-import-resolver-typescript#431 (comment).