Praise be to Allah.
It is better for a Muslim to avoid using vessels that are used in the cooking of pork and drinking of alcohol, but if he cannot find anything else then it is permissible for him to use them on condition that he wash them with water before use.
It was narrated from Abu Tha’labah al-Khushani that he asked the Messenger of Allaah (blessings and peace of Allah be upon him): We live close to some the people of the Book and they cook pork in their pots and drink wine in their vessels. The Messenger of Allaah (blessings and peace of Allah be upon him) said: “If you can find something else, eat and drink from it. If you cannot find anything else, then wash them with water and eat and drink.”
Narrated by Abu Dawood (3839); it is also narrated in al-Saheehayn.
See also the answer to question number 65617.
We do not think that things are so difficult for Muslims nowadays that they cannot find anything from which to drink juice except from wine glasses.
Moreover, if he drinks juice from a wine glass this opens the door to slander against this person who is drinking. Anyone who sees him may think that he is drinking alcohol. What the believer should do is close every door that may lead to people gossiping about him.
But if the intention of the one who drinks from a wine glass is to imitate those who drink alcohol in the way they drink, then in that case it is haraam to drink from that glass, because imitating people who are evildoers and immoral is something that is haraam.
See the answer to question number 119530.
And Allah knows best.