Let’s look at important things here –
Moon - Moon represents Mind, Emotions, Mother, Local Government, Peace of Mind, Home Environment, Water, Milk etc.
Purva Phalguni - Purva Phalguni is nakshatra of Luxury, Wealth and Lavish Life. It is also nakshatra of creative pursuits and love/romance. For detailed information, please check this - https://www.astrosaxena.com/ppnaksh.
Leo - As Purva Phalguni is a part of Leo, Leo sign and its representations become important. Leo is 5th sign of zodiac belt, hence it represents the things associated with 5th house of horoscope like Love, Creativity, Arts, Being on Stage etc. Besides that, Leo is basically the Lion. This is the sign of feeling like King or Queen. Also, it is a sign of independence, Confidence, Ego, Self Esteem etc. Leo is consisted of 2 and half Nakshatra namely Magha, Purva-Phalguni and Uttara-Phalguni. Leo's lord is Sun..
Sun - As Sun rules Leo, Sun's position and dignity is important to know about the overall functioning of any planet in Purva Phalguni/Leo.
Venus - As Purva Phalguni is ruled by Venus, Venus's position and dignity will also have an important role in functioning and results of any planet in Purva Phalguni.
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 Moon in Purva Phalguni Nakshatra – As Purva Phalguni is nakshatra related with creativity, Moon in Purva Phaguni shows a very creative mind. This is where the creative energy of Leo and Purva Phalguni comes together and impacts native's mind. So, this person can be very creative and must follow his creative pursuits in life/career as there he will get peace of mind. Also, as Purva Phalguni is nakshatra of lavish life, conveniences and luxuries etc, it shows a mind which loves to live a luxurious life. As love making is important part of this nakshatra, it can be termed as a very romantic mind too. They can love arts, media and movies especially romantic movies. These people can be equally good at fiance and wealth related matters and can make their career in financial side too. But as discussed above, peace of mind will be in creative pursuits and following a creative life path.
Role of Sun – Sun placement is important to guide Moon in right direction, being Leo's lord..
Role of Venus - Likewise, Venus placement is important to guide Moon in right direction, being Purva Phalguni'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 Moon in Purva Phalguni. So, we always need to take a holistic view of chart rather than just 1 planetary position.
Conclusion – So, this is how I see Moon in Purva Phalguni can work in a chart.