Combine water, sugar, and salt in the bowl of a stand mixer fitted with dough hook. Sprinkle yeast on top and allow to sit 5 minutes.
Add flour and butter. Mix on low speed until combined. Increase to medium speed and knead until the dough is smooth and pulls away from the side of bowl, approximately 5 minutes.
Place dough in well-greased bowl, cover with plastic wrap, and sit in warm place for 50-60 minutes until the dough has doubled in size.
Line 2 baking sheets with parchment paper and spray with nonstick spray. Preheat Air Fryer at 400 degrees F.
In large stock pot or roasting pan, combine 10 cups of water and the baking soda and bring to a boil.
Place pretzel dough onto an oiled work surface and divide into 8 equal pieces. Roll each piece of dough into a 24-inch rope. Cut each rope into bite-sized pieces, a little over an inch long.
One-by-one, place each pretzel into the boiling water for 30 seconds. Remove from water and place on parchment-lined baking sheet.
In batches, place pretzels in single layer in the basket of Air Fryer. Cook 3 minutes then shake basket to redistribute pretzel bites. Cook another 2-4 minutes until golden brown.
Remove pretzels from Air Fryer. Melt butter in small bowl. Combine sugar and cinnamon in a zip-top baggie. Dip pretzel bites into melted butter then place on piece of waxed paper for a minute or two to let the butter soak in. Sprinkle with salt*.
Put buttered pretzel bites into cinnamon and sugar bag then shake to coat. Remove pretzels and place on waxed paper.