As a Jyotish astrologer, I can see that the placement of retrograde Mercury in the 6th house in Leo sign can bring some challenges and opportunities. 

Firstly, retrograde Mercury in Vedic astrology is considered to have a weak and unpredictable nature, which can affect communication, analytical abilities, and decision-making processes. This planetary placement can create confusion in one's daily routines and mental processes, leading to miscommunications and misunderstandings at work.

However, the positive side of having retrograde Mercury in the 6th house is that it can provide the person with a deep understanding of health and healing, especially in service-oriented professions. They can connect with others through mutual work and develop great problem-solving skills to overcome daily obstacles.

Furthermore, having Leo sign in the 6th house brings a strong sense of pride and confidence in one's abilities, but it can also lead to stubbornness and ego clashes at work. The person can excel in creative fields and leadership roles, and their attention to detail can ensure success in their ventures.

Overall, the retrograde Mercury in the 6th house in Leo sign requires the person to be cautious and mindful of their communication, while utilizing their analytical skills and attention to detail to overcome daily challenges at work.

retrograde Mercury rules 4th and 7th house is in 6th house in Leo