Combine the chicken thighs, salsa verde, green chiles, chopped garlic, jalapeño, garlic powder, onion powder and cumin in a 6- to 8-quart slow cooker. Stir to evenly combine. (Don’t add salt now; jarred salsas are often high in sodium.) Cook on low until the chicken is tender and the flavors are blended, 5 to 6 hours. (If you will be away for 8 hours or more, set the cook time for 4 hours on low and set the slow cooker auto-switch to warm for the remaining time.)
Use two forks to coarsely shred the chicken. With the heat on low, add the scallions and cilantro, and stir to combine. Season to taste with salt and lime juice. Serve with rice or in tortillas, if desired, with accompaniments.
I used chicken breasts instead of thighs. They may be easier to shred.
This has a tendency to be very liquidly. Probably Ok for putting on rice but for tacos, I would consider thicking with a cornstarch slurry.
Also the cooking time an be speeded up by using an instant pot instead of a crock pot.