[{_id:"1",users:["1@abc.com","2@abc.com","3@def.com"]},{_id:"2",users:["1@abc.com","2@def.com","3@def.com"]}]

db.collection.aggregate([{$set:{users:{$filter:{input:"$users",cond:{$not:{$regexMatch:{input:"$$this",regex:"(?:@abc\\.com)$"}}}}}}}])