Grendel’s Mother (Beowulf) in human form.
As vampires, Drusilla and Darla (Buffy the Vampire Slayer/Angel) can freely shift between a human face and a vampire face.
A Slitheen unmasking (Doctor Who)
Using Transformation Magic, Carla (Fairy Tail) is able to assume a human form, albeit retaining her cat ears and tail.
Chocolina (Final Fantasy) is a chocobo granted the power to assume human form by Etro.
As a Lich, Pious Augustus (Eternal Darkness: Sanity's Requiem) often uses magic to shapeshift into a less threatening human form to better manipulate people...
...such as when he disguised himself as the monk Phillipe Augustine to take control of the Inquisition chapter of Amiens...
...and the antique collector Paul Augustine to trick Edwin Lindsey into helping him find the Essence of Mantorok in Cambodian.
Virasians (Gamera vs Viras) in their human forms.
Thanks to Puck's magic, Demona (Gargoyles) becomes a human during the day rather than entering stone sleep
Benares (Honkai Impact 3rd) transforming into a human.
Zim (Invader Zim) keeps his true identity secret through creative (and shoddy) disguises.
Kor (Jak and Daxter) has two forms, his true Metal Head form...
Lila (The Life and Times of Juniper Lee) using the Exfoliax Charm to gain a human form.
Greys (Marvel Comics) such as Rollo can disguise themselves as humans through Image Inducers.
As a highly advanced Sentinel, Nimrod (Marvel Comics) can assume the appearance of a human.
Being a mermaid herself, Lucia Nanami (Mermaid Melody) gains a human form when she's on dry land.
Hippo (Mermaid Melody) has three forms, his human form, his penguin form and...
...his true form, Hippocampus.
Latias (Pokémon) in her human form.
Duck (Princess tutu) transforming into Ahiru.
Crystal and Amber (Scooby-Doo and the Alien Invaders) in human and dog form respectively.
Snake demons Susu and Qingqing (The Sorcerer and the White Snake) take semi-human forms.
Mamitas (Space Dandy), as a Deathgerian, can take on the appearance of a young woman to attract prey.
Octus (Sym-Bionic Titan) can use hard light holograms to disguise himself as a human.
Utroms (Teenage Mutant Ninja Turtles)
Like all the Changelings, Stricklander (Trollhunters) is able to choose between his human and troll form.
What Soul Eater (Valkyrie Crusade) actually is is a complete mystery, she decides to appear with a female humanoid form.
While he is actually a demon resembling a giant bear, Rein (Zatch Bell!) has the ability to disguise himself as a human.
Pavo (Lightman) was Alcyonite he can disguise as human...
...than he can to be his Alcyonite form.
Certain Spirits (Seirei Tsukai no Blade Dance) of the highest-class like Restia and Est have human forms with high-level Elementalists being able to tell whether or not they're spirits are not.
Kon can disguise as human
Terminators (Terminator series), like T-800s, have living human tissue covering their metal endoskeletons, as a disguise for them pass through human and infiltrate their targets.
Starlings (Star Darlings) Must blend in on Wishworld During their Mission