Hello. I believe I can be of help to you with this issue. Your daughter is struggling to find her sense of identity and to attract particular reactions from particular types of people by altering her appearance as she does. The bot***** *****ne is that a good deal of her adornment will eventually become self-limiting, and she will indeed, have a rude awakening once she graduates and has to find work. If you are subsidizing her financially a great deal, you might want to think about cutting back on this and insist that she get a part time job NOW, as this will start her on the road to feedback from people who have money to hire her, but won't because of her appearance. It would be good for her to start experiencing the consequences of her actions at this time.
She will probably have to have plastic surgery to repair her earlobes someday, if she decides she has to do this or wants to do it. I have a close relative who now, at age 30+ realizes he needs to get his armband tatoos removed and is going through the process of doing this. Here is the difficult part for you right now: you are feeling panic
because you have run out of ideas for persuading and influencing your daughter and I suspect, you realize your relationship with her is deteriorating because of this issue. The fact is, there is likely nothing you can say to persuade your daughter to not tattoo herself further or stretch her earlobes, given that she is now 19. You have made your opinion known and she has heard it. So, it would be wise to hold fast to your personal values, but stop trying to convince her to change her ways right now; it is actually best right now to try your to maintain high quality communication with your daughter, despite your disapproval of her appearance. If you press an issue with her over which you have no control, you risk damaging your relationship with her further. On the other hand, your other daughter is dead wrong about suggesting that you compliment her on how cools she looks. Complete nonsense on this one.
You may be able to gain a bit of 'peace of mind' by realizing that appearance fads come and go and teens tend to become much more conservative in their dress and appearance, as social pressures to conform mount daily, after they leave college. The odds are that your daughter will HAVE TO moderate her appearance or change it altogether, if she ever hopes to get a really good job with a mainstream company, or attract a driven, quality man who can generate a good income for her family. Such men also tend to be reasonably conservative in dress and don't want their partner looking like an advertisement for a tattoo parlour.
I will pause here and solicit your reaction to this post.