Let’s assume that you want to create such a thing; and let’s assume that you’re not an idiot Hollywood producer who wants to use LOTR as toilet paper.
The halfling tribes that migrated into the Shire are known as the Harfoots, the Fallohides, and the Stoors, and they were led by the brothers Marcho and Blancho.
This is a JOKE, or a historical/linguistic reference (if you prefer) on the Germanic tribes that migrated to Britain and turned it into England. The Fallohides are a joke on the fairhaired Angles, and the Harfoots and Stoors are probably the Saxons and Jutes. Marcho and Blanco are both words meaning “horse,” and they reference the Saxon brothers Hengest and Horsa (two names also meaning “horse”).
The Jutes (aka the Eotas, Eudoses, Juti, or Jotar) may have included some Celtic Cimbri in their ancestry, but they were mostly from the Gutones (proto-Goths), Teutones (Celtic Germans – a different branch of Celt from the Irish and Scots), and Harudes (Germanic guys). The Angles we don’t know about much, but they were another Germanic tribe. The Saxons ditto, although we know they did a ton of sea raiding, to the point that their tribe name became a synonym for this kind of activity in late Classical times/the early Middle Ages.
So basically we are talking about TOTALLY CAUCASIAN PEOPLE. But mostly these are Caucasian people who would have come off the steppes into Europe within the last thousand years before the Romans came to Germany and told us about them, or which had come off the steppes somewhere in the Bronze Age.
They migrated to England as part of the disorder during the early Middle Ages, and especially because there was crowding and famine in their bit of Germany/Scandinavia, as the Roman Warm Period was over and the growing season in northern latitudes was a lot shorter.
Similarly, the Hobbit tribes apparently came off the steppes of Rhun at some point in the Third Age, and moved into the valleys of the Anduin. Some were still there, just in time for Smeagol’s cousin Deagol to find the One Ring (in about year 2463 of the Third Age) which had been lost by Isildur (in the 2nd year of the Third Age).
But by that time, the three tribes had already crossed the Misty Mountains and gotten permission to settle the Shire, in 1601 of the Third Age, from King Argeleb II of Arnor. (Unlike Hengest and Horsa with King Vortigern of Britain, they did not go on to take over the whole Kingdom of Arnor, or use a daughter for court intrigue.)
So for values of this joke, the “valleys of the Anduin” equals “forests and river valleys of Germany,” basically.
Now that we have explained a joke that used (what used to be) common historical knowledge for every American and UK schoolchild….
Clearly there are some Hobbits who dislike water and fear the Sea, but others (like Frodo and Gollum) who like swimming and boats. If the Saxons could become sailors and sea raiders, then theoretically some of the Anduin river tribes of halflings could also have done it.
If they were roaming around the world killing people with their deadly slings (a Hobbit specialty), and stealing their stuff, they were probably stealing people, too. So sure, they could theoretically have stolen a bunch of short proto-Maori and proto-Arab and prehistoric African girls and boys, using them and/or selling them for slaves and concubines, just like the Saxons and the Irish raiders and the Norse vikings did.
So if you are willing to accept that all those hippie Harfoots of color on the new Rings of Power show are actually the (fairly recent, since this is the SECOND Age) descendants of pirate Hobbits and pirate slave humans… okay. Fine.
Must be drenched in blood and villainy. Must have been marooned by the other pirate Hobbits, probably for being worse than them.
Or maybe they’re escaped slave Hobbit kids, wandering the world because they don’t want to go back to the sea-raiders.
Alternately… some halfling tribesmen could have served as Numenorean auxiliaries, particularly as slingers. This could have allowed them to meet and marry short human women of various heritages, and then bring them back to the tribe at the end of their hitch.
Or they could have been halfling tribespeople kidnapped and enslaved, taken to Far Rhun by the slavers along the prehistoric silk road, who met and married other Far Rhun slaves of various colors, and then got out of Far Rhun, headed for their ancestral home, found that the halflings had been pushed out, and kept going until they got off the steppes and into western lands.
Whatever way you picture it, there is no reason to believe that non-Caucasian halflings would ever have come to the Shire, because there’s no evidence of non-Caucasian halflings in Bilbo and Frodo’s time. Given the obsession of Hobbits with genealogy, and the topic of discussing the odd habits and appearance of Hobbits outside Hobbiton, we surely would have heard of Hobbits with different skin colors and hair textures.
OTOH, Middle Earth is wide, and any tribe of halflings could have ended up anywhere. This would provide much more story possibility than trying to shoehorn invisible, forgotten POC Hobbits into the history of the Shire.