Or you could use another field(invisible and dummy many2many field) to filter the prodlot_id based on this new field, the value of that field you need to compute using the onchange itself, instead of returning a domain for the one2many field you need to return the value for the whole field dummy, but you don't return a new domain, your field domain is using the dummy field as a filter

add one more condition to your domain, using AND operator, something like:  

[ '|','&', ( ...your condition... ), ('prodlot_id','in',[ id_of_record_to_apply_domain_to ]),('prodlot_id','not in',[ id_of_record_to_apply_domain_to ])]

If you want to have different domain per record, I'm afraid that it should not be possible by setting domain using onchange. most probably computed one2many field is the appropriate solution to your requirement in this case, rather then change domain of field. if you want to have different one2many list per record, then make this one2many field computed field and apply your application logic inside compute function in order to have correct list per record.