Hiatal hernia produces disnea?

Depends. If one has a very large hiatal/ Para esophageal hernia, big enough to compress on airways, then it can cause dyspnea, in some cases if it is causing significant reflux specially silent one , it can damage the lungs with silent aspirations and can cause atypical symptoms.
Maybe, depend.... Pulmonary function may be affected leading to dyspnea if hiatal hernia is large enough to impair lung expansion at inspiration, especially in someone with already marginal pulmonary functional reserve. So, ask your doctor so to discuss individual variation and significance. Best wish to health...