I have found several medical websites that discuss using this very process to clear pressure form the inner ear. However there are other methods mentioned as well so for those interested below are a few links. each of which by the way recommend using the Valsalva method.
https://www.healthline.com/health/how-to-unclog-ears#middle-ear
https://www.healthline.com/health/how-to-get-water-out-of-your-ear#removing-the-water (see step 10)
https://www.webmd.com/allergies/stuffy-ears-sinuses#1
https://www.wikihow.com/Unclog-the-Inner-Ear-or-Eustachian-Tube
https://www.healthline.com/health/how-to-unclog-ears#middle-ear
https://www.healthline.com/health/how-to-get-water-out-of-your-ear#removing-the-water (see step 10)
https://www.webmd.com/allergies/stuffy-ears-sinuses#1
https://www.wikihow.com/Unclog-the-Inner-Ear-or-Eustachian-Tube