In a spherical environment and neglecting interactions, yes. Actually, even neglecting interactions if you include relativistic corrections (spin-orbit coupling) the 10 d orbitals will split into groups of j = 3/2 and j = 5/2, with different energies, although maybe only slightly different.
Once you include interactions, even in a spherical environment, no. Hund's rules give a specific order for filling the orbitals, and this is because other fillings will be higher in energy.
The simplest answer is Yes.
All the orbitals of any d-subshell are degenerate.
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