Let’s look at important things here –
Moon - Moon represents Mind, Emotions, Mother, Local Government, Peace of Mind, Home Environment, Water, Milk etc.
Moola Nakshatra - It is a nakshatra of research, digging deep and knowing the hidden truth of things and people in life. For more information on Moola Nakshatra, please read this - https://www.astrosaxena.com/Moolnaksh .
Sagittarius - As Moola is part of Sagittarius sign, Sagittarius and things represented by Sagittarius are important here. Sagittarius is the 9th sign of Zodiac Belt, hence it represents many things related with the 9th house of horoscope like Religion, Knowledge, Wisdom, Higher Learnings, Gurus, Teachings from your Father etc. Besides it also represents Coaching, Universities, Professors and Preachers, Higher Wisdom, Written Law of the Land etc. Sagittarius has 2 and half nakshatra which are Mula, Purva-Ashadha and Uttara-Ashadha. Sagittarius' lord is Jupiter.
Ketu - As Ketu rules Moola, Ketu's position and dignity is important to know about the overall functioning of any planet in Moola.
Jupiter - As Jupiter rules Sagittarius, their position and dignity is important to know about the overall functioning of any planet in Moola/Sagittarius.
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 Moola Nakshatra – Now, Moon is coming out of Scorpio debilitation but Moola still holds some of the attributes of Scorpio. Both are ruled by Ketu. Moola is also a Gandmool Nakshatra and Gandanta Point just like Jyeshtha in Scorpio. So, by no means Moon is in pleasant position when it is in Moola.
Now, Moon represents Mind and Moola is all about research and investigation. Hence, Moon in Moola creates someone who has a very research oriented mind. In any field of work or study, they would be inclined to do research activities. It also gives great interest or inclination towards occult, spirituality and mysticism. As Moola is ruled by Ketu which represents isolation and separation, it may make them live or feel separate/isolate from their Mother. They may even feel that their Mother is not fair towards them. Same sort of separation feeling will be there for the people represented by the house which Moon rules. Like, if Moon rules 3rd house, they can feel separation from their younger sibling. At the same time, as Ketu represents past life connection, it shows that they may have some past-life karma left-over with their Mother. Also, they can have emotional issues from childhood and meditation can help a great deal. They are normally seen in research, medicine or occult field. As it is part of Sagittarius, they can be Teachers and Counselors too. Again, they inherit all these qualities from their Mother.
Role of Ketu – Ketu placement is important to guide Moon in right direction, being Moola's lord.
Role of Jupiter - Also, Jupiter placement is important to guide Moon in right direction, being Sagittarius 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 Moola. 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 Moola can work in a chart.
Hope this helps. Please post any comment or query you may have.