I’m not even sure if “without hosiery” is the correct term to refer to wearing heels with nothing on your feet, or if you would say “barefooted”. I don’t know, I’m a man and I’m not familiar with the terminology here. 

What I do wonder is if someone knows whether this was allowed before Vatican 2. 

It’s one thing to have nothing on your feet and wear those ugly sandals that are all broad, with thick soles and usually made of leather, you know like the ones you see religious people wear. I’m not talking about those. I’m talking about heels and other flat footed shoes/sandals that are very “attractive” and showcase the feet (assuming they have nice feet). It seems to me this is just not appropriate for Mass because it seems sensual, showing off flesh. 

I’ve noticed younger girls wear the same kind of heels/open shoes but with hosiery with lace and stuff and that actually looks nice, not in a sensual way. 

Anyway, hope this wasn’t too awkward. 

As far as I know, the Church has never condemned barefeet.

It is very difficult sometimes to draw a line and separate what is feminine and what is immodest. There is a question of culture and custom too.

I have a liking female feet, but, for me at least, ugly sandals won't make me uninterested. Nice feet are nice feet, no matter the woman is wearing.

Feet are not considered indecent, as you can see on every Moral Theology manual.

If you have a particular attraction to them, you need to find a way and work around it.

Women are usually not wearing indecent clothes at mass, so, you might be safer looking up than down. It is not like they are wearing bikinis and the only safe place to look is the ground.

Of all the things to think about when going to Mass, whether a woman has stockings on or not is ridiculous.   Let's worry if a man is wearing a tie or not. PAY ATTENTION TO THE ALTAR & NOT THE WOMEN.

This matter is culturally relative, unless your notion of the Church is solely 1950s USA.

  Have you some sort of foot fetish? 👣 Or is there a particular female who shows too much leg? Perhaps it’s time to fix your gaze elsewhere!  🦵🏾🦵🏾 👀 ????

I think I read somewhere that Padre Pio made women wear solid colored thick stockings to the top of the thigh, bloomers, and hemlines at least 8” below the bottom of the knee.  (How such a thing could be monitored beyond the hem length, however, I don’t know unless God told him.)  
No, I do not recall there being Padre Pio rules in place pre-V2.  

I CAN say that women and girls generally wore some kind of hosiery for Mass or dress-up  unless one’s skirt was fairly long. Little girls wore tights, knee socks, or bobby socks. Older girls and women wore stockings, pantyhose, or knee-highs. Casual sandals like flip-flops, play shoes, or sneakers, just weren’t worn to Mass.  The same applied to men.  Unless you were a member of a discalced religious order, men didn’t wear sandals to Mass.  As for seeing men’s legs, that was never an issue because all but very young boys wore long pants.  If a young boy wore shorts, they were part of a suit and always included knee socks and shoes, such as one still sees in some Caribbean countries.  

If the people come to Mass with too much leg showing, flip-flops or recreational footwear, short skirts or shorts on men and boys, do speak with your priest.  In the meantime, keep your eyes on the altar, your missal, and your Rosary!  

 It is not sinful for a woman to not wear stockings to Mass.

 It is sinful for anyone to stare at her bare feet and feel lust.

Now I would say that how a person dresses themselves can scandalize others, it does seem a bit extreme that someone would feel lust from someone's feet... Also some men might find a women more attractive when they are wearing stockings/nice shoes.

I'm speaking in general.  I'm not going to list ever scenario that a man might feel lust.  Men have lusted after aged cloistered nuns after all.  

It's a given that all women should practice modesty at all times.  A modestly dressed woman wearing open shoes with no stockings commit no sin if no other sinful behavior is committed.  The lusting man commits the sin.

"Before Vatican 2" includes lots of centuries when women's hemlines were long enough to cover their ankles. If they wore hosiery, for most it was a basic necessity, not a fashion statement. 

Rather than idly checking out feminine footwear, try to keep your eyes on the altar or read some short devotions. And since there's no limit to the form that distractions can take, this can apply to anyone whether male or female.