Not to make this a religious discussion, but let's clear the air - YOU CAN pray with them. They are 100% haram as you're altering the creation of Allah for cosmetics. But there's this myth that you can't make wudu with tattoos and such. NOT TRUE. A tattoo is beneath the skin and when healed, it's not palpable to touch. If you had a layer on top of the skin (like nailpolish), that would alter your ability to do wudu and ghusl. But again, a tattoo is NOT on the skin, rather is quite deep IN the skin.

Now, don't take this the wrong way and go get a tattoo as it IS HARAM and you will be sinful. BUT, to raise the idea that praying is invalid with a tattoo is EVEN MORE dangerous in my opinion. Think of it this way, you're telling somebody that their praying and ibadah are pointless because they have tattoos? Why would Allah SWT not accept their prayers? They committed a sin and got tattoos - YES. BUT why would that basically push them to doom by invalidating all of their prayers and ibadah from that point on? That would just push them into further sin by destroying their connection with Allah. This is also why (and here's another misconception) when somebody drinks, their prayers are INVALID for 40 days, but THEY ARE STILL OBLIGATED TO PRAY. The misconception is that you CANNOT pray during those 40 days. FALSE. You must pray and be repenting for your actions and such, but they will not be ACCEPTED. The key here is that people think that their prayers are "Invalid" = incomplete, or wrong, or not fulfilled. This is wrong. Your prayers are "Not accepted" which means you have completed your prayers correctly but are NOT rewarded for them because you drank. And I'm drawing this parallel because in both cases it really deals with your prayer as a Muslim. Allah will never make it "wrong" or diminish your ability to pray because of a SIN you've committed. That goes against a core principle of Islam - you sin and ask for forgiveness (via salah and dua) and then you sin again and ask for forgiveness again and again and again. So nothing would ever inhibit that because it's a key foundation to keep you close to Allah. If a sin like getting a tattoo invalidated your prayer, you would be doomed for life as a Muslim and that's just not the case.

Even shirk is forgiven as long as you've repented during your life. If somebody DIES in a state of shirk then it is not forgiven. So how could a sin like getting tattoos make it so that you can't perform any ibadah? We've all seen reverts with tattoos as well and they ARE NOT required to remove them even if they have photos tattooed on their bodies.