In reply to ABD_91:
It does not really matter if it is uvm_sequence or uvm_sequence_item, as are both inherited from the uvm_object.
Look at the next link of inheritance:
https://verificationacademy.com/verification-methodology-reference/uvm/docs_1.1c/html/files2/sequences-txt.html
I specifically asking how to override a uvm_object which does not have a position in a testbench as it does not has a parent.
And the function set_inst_override is present only under the uvm_component source code.
Open the UVM uvm_object file and look after set_inst_override, you won’t find it.