### No, grapple and shoving attacks can be performed on creatures only.

You quoted the relevant rules: both attacks require that the target be a creature.

In particular, about your listed entities:

- *Bigby's hand* is an object, not a creature: it can grapple because its description says so, under the [*Specific beats general*][1] principle.
- *Guardian of Faith* is neither a creature, nor an object. It does not provide any stats block, nor point to a Monster stats block. Moreover, the spell description does not provide any partial stats (AC, HP, attacks) that might suggest a DM ruling in that sense.
- Spiritual Weapon is...a weapon. You can check the difference with a [Flying Sword][2], which is technically a creature and hence can be grappled and/or shoved.
- Unseen Servant is not a creature either.


  [1]: https://www.dndbeyond.com/sources/basic-rules/introduction#SpecificBeatsGeneral
  [2]: https://www.dndbeyond.com/monsters/flying-sword