In a large bowl, whisk together the buttermilk, maple syrup, salt, and pepper.
Add the chicken tenders to the bowl and stir until they're completely coated. Let the mixture sit at room temperature for 30 minutes, or cover the bowl and refrigerate overnight.
In a bowl or shallow dish, mix the panko breadcrumbs, everything bagel seasoning, and a pinch of salt and pepper.
Working with a few pieces at a time, remove the chicken from the marinade. Let any excess drip off, then dredge in the panko mixture. Press gently but firmly so that the coating sticks. Repeat with the remaining chicken.
Preheat your air fryer to 400°F, then spritz the fryer basket with cooking spray.
Arrange the chicken tenders in a single layer, leaving a little space between them for proper airflow. Spritz the tops with more cooking spray.
Air-fry the chicken in batches for 10 to 12 minutes, turning once halfway through.
While your chicken cooks, stir together the whole-grain mustard, Dijon, and honey in a small bowl. Feel free to add more honey if you'd like it sweeter.
Transfer the chicken to a plate or wire rack and let them cool for about 10 minutes. Serve with the honey mustard dip and enjoy!