The position of Sun in the 7th house for a Libra ascendant is considered to be an auspicious placement. Since Sun is in its exalted state, it brings with it a lot of positive energy and enhances the characteristics of Libra ascendant.
Sun is the lord of the 11th house in this placement, which indicates that the native will have a strong desire to succeed and will work hard towards achieving their goals. They will have good business acumen and may even excel in entrepreneurship. The presence of Sun in the 7th house also suggests that the native's spouse may hold an important position in their professional life or bring financial gains.
As Sun governs the 1st and 10th houses by nature, its placement in the 7th house can have a positive impact on these houses too. The first house represents one's personality, physical appearance and overall health. With Sun's aspect on this house, the native is likely to have a charming personality, good looks and robust health. They are likely to be highly self-confident and possess a natural leadership quality.
The tenth house signifies one's career and profession. With Sun as its natural karaka, its placement in the seventh house ensures success in their chosen career path. However, if they face setbacks at work due to external factors beyond their control, they may become restless.
The aspect of Sun on the first house can also make them dominating or aggressive at times which can impact their relationships negatively unless they manage it well.
Moreover, Sun’s aspect on 9th House also indicates foreign travel possibilities for higher studies or out for employment purposes.
In conclusion, an exalted Sun in the seventh house is extremely beneficial for those with Libra as their ascendant sign. It enhances their overall personality traits such as confidence and natural leadership qualities while ensuring success in their chosen profession due to good decision-making abilities and excellent negotiation skills required for related success factors like partnership, diplomatic tasks etc. There might be some concerns with aggressive behavior which should be work upon for smooth relationships.