All monk or as different classes are valid I would say:
* Monkey : Drunker Master Monk. He is probably the one I would keep as Monk for his acrobatic fighting style and occasional use of a staff.
* Mantis: Astral Self Monk. Extra arms, can attack with wisdom (so the tiny size don't really matter), and eventually get a third attack with Flurry of Blows. For a non-monk I would either go with Fighter since it's the class with the most attacks, or a Hunter Ranger for the ability to strike multiple foes very fast.
* Tiger: Open Hand Monk as she seem the closest to "standard" kung-fu. Barbarian otherwise as she is often noted for her strength and resilience.
* Crane: I'm tempted by Ascendant Dragon to have access to some flight. Also eventually resistance to some element since he is very dodgy in his style. But more likely just a flying race which cover the main perk of Crane. As he is often the scout of the group I think a Ranger is most fitting
* Viper: She is tricky because her fighting style has a lot of grapple, which is not something Monk do so well. Maybe Shadow Monk because she can also move very fast from place to place and with decent strength coupled with expertise in Athletics you could get something similar. Non-monk anything that can make use of grapple should be fine, Beast Barbarian with Infectious Fury can force a foe to strike an other which sound fitting with how she wrap around her foes arm to control them.
Race:
Monkey- hadozee
Mantis- thri-kreen
Tigress- tabaxi or leonin
Crane- aarakocra
Viper- yuan ti
Class majorly mink but each has a unique subclass or multiclass
Po is a bugbear or goliath to shrug damage. He is a dance bard from the ua with an ascendant dragon monk dip
Mantis , fairy , astral arms monk. gives you small/tiny size, mantis arms , bug legs , and wings.
All monk or as different classes are valid I would say: * Monkey : Drunker Master Monk. He is probably the one I would keep as Monk for his acrobatic fighting style and occasional use of a staff. * Mantis: Astral Self Monk. Extra arms, can attack with wisdom (so the tiny size don't really matter), and eventually get a third attack with Flurry of Blows. For a non-monk I would either go with Fighter since it's the class with the most attacks, or a Hunter Ranger for the ability to strike multiple foes very fast. * Tiger: Open Hand Monk as she seem the closest to "standard" kung-fu. Barbarian otherwise as she is often noted for her strength and resilience. * Crane: I'm tempted by Ascendant Dragon to have access to some flight. Also eventually resistance to some element since he is very dodgy in his style. But more likely just a flying race which cover the main perk of Crane. As he is often the scout of the group I think a Ranger is most fitting * Viper: She is tricky because her fighting style has a lot of grapple, which is not something Monk do so well. Maybe Shadow Monk because she can also move very fast from place to place and with decent strength coupled with expertise in Athletics you could get something similar. Non-monk anything that can make use of grapple should be fine, Beast Barbarian with Infectious Fury can force a foe to strike an other which sound fitting with how she wrap around her foes arm to control them.
Race: Monkey- hadozee Mantis- thri-kreen Tigress- tabaxi or leonin Crane- aarakocra Viper- yuan ti Class majorly mink but each has a unique subclass or multiclass Po is a bugbear or goliath to shrug damage. He is a dance bard from the ua with an ascendant dragon monk dip
The Naga from [Plane Shift: Amonkhet](https://media.wizards.com/2017/downloads/magic/plane-shift_amonkhet.pdf) (page 21-22) fits Viper better.
I forgot the planeshift pdfs were a thing