What races and classes could be used as a disguise.

[narrator667]

I love playing characters with identity issues or who wear a lot of disguises.
A Lizardfolk fighter pretending to be a Dragonborn Paladin as he thinks of himself a swamp savage when he'd rather give people hope.
Lesser born half-orc hexblade pretending to be a cultured hobgoblin eldritch knight as he views them as self made gishes instead of innate power or power made through deals.
I just know I'll be able to make something between the Dwarves, gnomes, and halflings. But I'm a bit uninspired by them at the moment. Any other ideas? Have you ever played a character like this?

[Nifft]

If I wanted this to be a thing, then what I'd do is make some well-known NPC roles like Ducal Mage-Knight, and have that be a thing with some NPC powers which don't work exactly like PC powers, but a bunch of different types of PC could probably fake it.

I wouldn't make PC classes so well-known in-game that NPCs would think or talk in game terms.

[Ventruenox]

This is part of my character concept for the next campaign. A V-human who takes his first level in Rogue with the Charlatan background, then poses as an elf for credibility to sell a fake religion. All further levels are taken in UA Order Cleric, and to his surprise as much as anyone's, his prayers and spells actually work. (Homebrewed alternate Earth setting where a forgotten minor Greek deity misunderstood his words, but it was the closest thing to a prayer she had in eons. Lawyers who used to pray to her all make Warlock pacts nowadays instead.) It should be fun becoming increasingly ridiculous with the space opera fiction theme to his gospel, whilst maintaining the facade that he isn't an elf at all. I'll RP him as a mixture of faith healer Benny Hinn (https://en.m.wikipedia.org/wiki/Benny_Hinn) and Foghorn Leghorn.

[thoroughlyS]

I've mused on the idea of a Firbolg that uses their innate disguise self to appear as an Elf as often as possible. Sadly the duration isn't long enough, but you could use it in towns. Tangentially related, I had the idea of an Aasimar Sun Soul that doesn't know he's an Aasimar. His angelic guide is a Lantern Archon, and he just assumes any contact is just him tapping into his "spiritual light within".

[tieren]

I had a Yuanti Pureblood who tried to pass herself off as a human dragon sorcerer.

She got elaborate tattoos to highlight/disguise her patches of scales, and if anyone asked she reluctantly explained that her family bloodline had been corrupted by a green dragon mating some generations ago and she still bears the marks of her ancestors dishonor.

(green dragon bit helped explain the immunity to poison too)

[Wilko]

Not race as such but i did build a sorcerer once who was for backstory reasons desperately trying to convince everyone he was a wizard

(He was studying to be a wizard, tried to take a shortcut, had an accident and ended up becoming a wild magic sorcerer, his aim was to get his magic under control and prevent anyone working out what happened...)

[Vorpalchicken]

Strap a bunch of goblins to your body to pose as some sort of aberration.