The meta_value of a post object field is either a Post ID or an array of Post IDs.
If you have the Post ID that you are looking for in that field, then yes. See this page https://www.advancedcustomfields.com/resources/query-posts-custom-fields/ under the array based values section. In this case you would use a LIKE query and search for
if on the other hand you want to do a search that is something like
=> posts your are searching => post object field => some value in the post selected in the post object field
then no, this is not possible. I supposed it would be with an extremely complicated MySQL query, but it is not possible using WP_Query().
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