How can i convert all object Ids to string using query in MongoDB, note the structure is complex, So can't use $toString in $addFields and $project?

I have a really deep-nested JSON object generated by aggregation query, but I want to convert all the object ids to string format. Tried $toString in $addFields and $project. Since the object is nested and contains an array of objects with object id. It's difficult to do using this. Is there any other way by which I can convert all object ids to string in MongoDB during querying?