How is the sea buckthorn oil pill compared to the oral hyaluronic acid pill for moisturizing body?

Both products are dietary supplements.

A. The sea buckthorn oil provides the following nutrients:

1. About 14 vitamins, including vitamin A, C, D, E, F, K, P, and B complex vitamins (B1, B2, B6)
2. Many carotenoids (beta-carotene, lycopene, cryptoxanthin, physalien, and zeaxanthin), phenolic (salicylic, p-coumaric, m-coumaric, p-hydroxyphenyl lactic acid, and gallic acid), and flavonoids (flavan-3-ols, catechin, epicatechin, gallocatechin, epigallocatechin, kaempferol, quercetin, isorhamnetin, myricetin, rutin, and proanthocyanidins).
3. Omega 3, 6, 7, and 9 fatty acids. Palmitoleic acid is an omega-7 fatty acid rarely found in plants, but sea buckthorn oil is one of the two plant-based sources of this unsaturated fatty acid. The other one is macadamia nuts. If you love nuts, add macadamia nuts to your daily diet can help support your vaginal skin health.
4. Except collagen proteins, sea buckthorn oil provides almost everything else to promote skin elasticity and mucus glands function to keep a good skin (and mucosa) moisture.
5. In addition to promoting healthy skin and moisturizing mucosa, sea buckthorn oil helps prevent heart attack, stroke, leaky gut, dry eyes, etc., and promote the body's immune system to prevent cancer and infections.

B. The oral hyaluronic acid pill provide no valuable nutrients

Hyaluronic acid is an anionic, nonsulfated glycosaminoglycan distributed widely throughout connective, epithelial, and neural tissues. Its molecule  can be very large: human synovial HA averages about 7 million Da per molecule, or about 20,000 disaccharide monomers. The human digestive system cannot absorb it due to its super large molecular size, unless it is degraded to small molecules. After degradation, it releases water, carbon and ammonia, with almost no nutritional value to moisturizing skin or having any health benefits. It is like a useless sugar pill.

Topical use of hyaluronic acid provide a good moisturizer because it is a good water trapper. It has been extensively used in cosmetic products. But it may relieve dryness but has no effect on reversing vaginal atrophy. A comparison is detailed in this article:

How is NeuEve compared with hyaluronic acid?