Let’s look at important things here –
Mars - Mars represents our will power, courage, ability to take actions, aggressive nature, anger, our fighting ability, brother, male friends, a boy friend for a girl, a soldier, an athlete and real estate etc.
Hasta - Hasta is nakshatra of healing, health care and skillful people. It also represents hard work. For more info on Hasta, please check this link - https://www.astrosaxena.com/hastnaksh.
Virgo - As Hasta is a part of Virgo, Virgo sign and its representations also become important. Virgo is the 6th sign of zodiac belt, hence it represents almost all the things which are represented by the 6th house of horoscope like Debts, Diseases, Obstacles, Serving the under-privileged, Service Life, etc. Besides this, Virgo represents analytical or critical nature of people, being perfectionist and healing abilities. Virgo's basic representation is the lady coming in boat with wheat and herbs in her hands. So, Virgo is basically a sign of healing. Virgo consists of next set of 2 and half nakshatra. i.e. Uttara-Phalguni, Hasta and Chitra. Virgo's lord is Mercury.
Moon - As Moon rules Hasta, Moon's position and dignity is important to know about the overall functioning of any planet in Hasta/Virgo.
Mercury - As Mercury rules Virgo, Mercury's position and dignity is important to know about the overall functioning of any planet in Hastai/Virgo.
Houses Involved – Also, we can’t afford to forget the houses involved as a planet can be ruling different houses and sitting in different house for every person as per ascendant and planet’s position. To know overall affect, we have to consider the houses involved as those areas of life are being impacted.
Interpretation of Mars in Hasta Nakshatra – Now, we are in middle portion of Virgo where any sign exhibits its maximum energy. Mars's actions and efforts are working inside Hasta realm. The common theme around Virgo and Hasta are that they both represent healing and health care. So, Mars in Hasta will show someone who puts his efforts and actions in health care related fields or healing others. As Mars and Hasta both represent hands, it can very well show a Reiki Healer. It also makes someone Palmist. Hasta can also open the door of teaching due to rulership of Moon but with Mars in Hasta, it is more a counselor or motivational speaker. This position also shows very hard working people but as Mars is in enemy sign, their efforts can be scattered everywhere. The biggest challenge for them is to streamline their efforts in one direction. They can be highly ambitious and would put any effort for achieving their ambitions. In matters of relationship, this position can be troublesome as Mars in Virgo/Hasta person can be dominating and controlling by nature. It can also give aggressive speech to someone. So, these are the things they need to work on and improve. Overall, it shows a very hard working person with strong will-power who doesn't accept defeat easily. It is just that they need to redirect that will-power and courage towards positive actions.
Role of Moon – Moon placement is important to guide Mars in right direction, being Hasta's lord.
Role of Mercury - Likewise, Mercury placement is important to guide Mars in right direction, being Virgo's lord.
Other Factors – And of course, we need to consider conjunction, aspects, house lordship, house position and dashas etc to know the exact results of Mars in Hasta. So, we always need to take a holistic view of chart rather than just 1 planetary position.
Conclusion – So, this is how I see Mars in Hasta can work in a chart.