I have found Héloise, a French astrologer based in The Hague, Netherlands to explain the 5th House regarding diplomats, ambassadors and agents.
https://www.heloastro.com/blog/diplomacy-fifth-house
"Now, let’s have a look at what Dorotheus of Sidon, one of the OG hellenistic astrologers that has transmitted us a lot of the original significations of astrology has to say about the triplicity lords of the 5th house:
1st triplicity lord: children & offsprings
2nd triplicity lord: pleasures, love affairs, drinking.
3rd triplicity lord: emissaries, messengers, giving or exchanging of presents."
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"The connection between the 5th house and diplomats is apparent through the signification of its 3rd triplicity lords: emissaries. The exchange of presents also points to the type of work which aims to both create allies and appease tensions. We can see here the mark of Venus, who rejoices in the 5th house Venus is associated with union and harmony, which are obvious in the work of ambassadors, but also with cleanliness and the tending of temples and sacred rites. Diplomats are messengers, emissaries of their own countries who are invested with an official mission of good relations and pacification. This mission is so important that they have dedicated buildings in foreign countries (consulates & embassies) that citizens of their own countries can come to for assistance."
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"Another interesting connection is through derivative houses: the 5th house is actually the 9th house from the 9th, which is interesting if you think of diplomats as foreign officials in a foreign country. I also like to think of the relationship of both these houses (the 5th and the 9th) to the 1st house: they all make a trine aspect (they are 120° apart) to each other. Since the trine is a supporting aspect, we see an interesting relationship here between the 9th house (where the Sun rejoices), the house of foreign lands, of the Gods and important religious ceremonies making a superior trine to the 1st — in the case of a state, foreign affairs playing a superior role in the place of the state — which in turns makes a trine to the 5th (chooses ambassadors and sending them abroad), which itself makes a superior trine to the 9th house (diplomats and ambassadors play a key role and influence foreign affairs)."
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"I’ve noticed that diplomats and people who work in foreign affairs usually have prominent 4th house placements. This is usually because in our modern worlds, they have to build a career in domestic affairs (the politics of their own country) before they venture into foreign affairs."
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"Speaking of eminence...
see chart of Antonio Guterres on the link above...
In order to calculate eminence, Vettius Valens gives the technique of looking at the triplicity lords of the sect light. For Antonio Guterres, his 5th house Taurus Moon is his sect light. The Earth triplicity lords at night are the Moon, Venus and the participating lord is Mars, in that order. According to Valens, planets that are in good condition and in angular houses (this is very important) are conditions of eminence: the first denotes the first part of life, while the second denotes the second part of the life. If succedent houses (such as the 5th) aren’t too bad in terms of ranking, they don’t necessarily denote eminence (meaning the person being elevated to a higher status that they otherwise started with). However, Valens also says that the participating lord can help the second triplicity lord (so later in life). In this case, Guterres has a 4th house (angular) extremely dignified Mars that comes to assist. If Guterres comes from a relatively modest background (succedent first triplicity lord, the Moon), although provided for, he accessed later in life to honours and eminence in the realm of international politics (his 5th Venus as the second triplicity lord, second part of life - diplomacy par excellence !). Not only that, but he did it through personal recommendations thanks to his background in international politics — symbolised by his 4th Mars as chart ruler! His lot of Spirit, in Capricorn in the 1st house is witnessed favourably by his Taurus stellium (which trines it) and its exaltation ruler Mars. Guterres is the perfect example of 5th house support and honours coming from the realm of the 4th house, so don’t sleep on that connection when it comes to the 5th."