Can you tell according to all schools of thoughts?I will maybe grow to become teamlead in my team. This means that every morning I will do a call about the daily tasks. In my team there are 2 non Muslim woman. There are more people in the team and sometimes some people in my team make haram and kufr and shirk jokes or sayings in the call. Will this be haram for me or worse then sinning kufr (may Allah protect us from this)? I don't ralk and laugh at that moment.What about if they ask free for christmas or for haram activities like parties. I need to approve the time off then. Will I be sinful if I do so? Because I don't want to, but it will be my role.

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

It is not permissible to participate and listen to calls that include forbidden or Kufr matters; rather, you must denounce that and tell them to stop, or stop the conversation with them.
Allah Says (what means): {And when you see those who engage in [offensive] discourse concerning Our verses, then turn away from them until they enter into another conversation. And if Satan should cause you to forget, then do not remain after the reminder with the wrongdoing people.} [Quran 6:68]

Ibn Taymiyyah said in Majmoo’ al-Fatawa:

“If a man listens to disbelief, lies, and backbiting, unintentionally, and he was accidentally passing by a road and he heard that, then, by the agreement of all the Muslims [Muslim scholars], he is not sinful. But if he sits and listens to it and does not deny it either with his heart, his tongue, or his hand, then, by the agreement of all the Muslims, he is sinful.” [End of quote]

However, the mere staying in such conversations is not disbelief, as long as the person does not accept disbelief and does not approve of it.

It is not permissible for you to help in the organization of forbidden occasions; being a team leader does not justify helping and participating in forbidden matters. Allah Says (what means): {But do not cooperate in sin and aggression. And fear Allah; indeed, Allah is severe in penalty.} [Quran 5:2]

Ibn Taymiyyah said in Majmoo’ al-Fatawa:

“If a man helps in the disobedience of Allah, then he is sinful because he helped in sin and transgression. It is for this reason that the Prophet cursed wine, its presser, the one who demands for it to be pressed, its drinker, its carrier, the one to whom it is carried, its server, its seller, its buyer, the one who consumes its price, its purchaser, and the one for whom it is purchased. Most of these, like the one who presses it, its carrier, and the one who serves it, help directly in drinking it.” [End of quote]

If by your question you are asking about the ruling on you agreeing to give your team a leave, and you know that their purpose in the leave is to hold a forbidden celebration, then it is safer not to give them leave on this day as long as you have the authority to do so, so as not to help them in sin, and this will be a kind of preventing evil.

For more benefit on helping in sin and transgression, please refer to Fatawa 290617, 336724, and 124718.

Allah knows best.