Is it permitted to apply face moisturizer on yom tov?
Someone who uses moisturizers every day can use it on Shabbat and Yom Tov.
Does the consistency matter?
Consistency does not matter because you are rubbing it into the skin.
How about all other skin care serums , sprays, creams which are part of one’s weekly / daily skin care routine ? Can they be used on Shabbos ?
That would be the same