What do spirit look like in the afterlife?
It is your spirit who will return "home" to the spirit world (heaven/afterlife), and you will most likely retain your appearance through the conclusion of your life review, a younger version if you die when elderly.
By the end of your life review, your identity will have merged with the permanent identity of your spirit but will likely remain near the surface for some time. It is your spirit who chose what to look like after their first few lifetimes, and they will resume that appearance, briefly switching back to yours when they meet your returning loved ones.
Spirits, being energy, do not have physical characteristics, but they assume appearances, rather like holograms, in order to relate better to the physical world. It is also, to some extent, how they recognize each other, but that is primarily by their auras, no two of which are identical.
Most spirits develop a gender preference and will choose a congruent appearance based on one of their first lifetimes or a composite. Some spirits choose to appear as gender neutral. Once chosen, a spirit will retain that appearance. Most choose to appear to be in the prime of life, but some choose to show a very gradual aging process.