Allitur (God of ethics and propriety) LG(N)
Atroa (Goddess of spring and the East Wind) NG, Oeridian origin
Beory (Oerth Mother, Goddess of nature, rain) N
Berei (Goddess of home, family, and agriculture) NG
Bleredd (God of metal, mines, and smiths) NC
Boccob (God of magic and arcane knowledge) N
Bralm (Goddess of insects and industriousness) N(L), Suel origin
Celestian (God of the stars, space, and wanderers) N(G), Oeridian origin
Saint Cuthbert (God of wisdom, dedication, and zeal) LG(N)
Ehlonna "of the forests" (Goddess of forests, flowers, and meadows) NG
Erythnul (God of hate, envy, malice, and panic) CE(N), Oeridian origin
Fharlanghn (God of horizons, distance, and travel) N(g), Oeridian origin
Geshtai (Goddess of lakes, rivers, and wells) N, Baklunish origin
Heironeous (God of chivalry, honor, justice, and valor) LG
Hextor (God of war, discord, and massacre) LE
Incabulos (God of evil, plagues, and nightmares) NE
Joramy (Goddess of fire, volcanoes, anger, and quarrels) N(G)
Lirr (Goddess of prose, poetry, and art) CG
Lydia (Goddess of music, knowledge, and daylight) NG, Suel origin
Myhriss (Goddess of love and beauty) NG
Nerull "The Reaper" (God of death, darkness, and the Underworld) NE
Obad-hai (God of nature, wildlands, freedom, and hunting) N
Olidammara (God of music, revelry, rougery, and wine) NC
Pelor (God of the sun, strength, light, and healing) NG
Pholtus (God of light, resolution, and law) LG(N), Oeridian origin
Procan (God of the oceans, seas, and salt) NC, Oeridian origin
Rao (God of peace, reason, and serenity) LG
Ralishaz (God of chance, ill-luck, and misfortune) CN(E)
Sotillion (Goddess of summer, the South wind, ease, and comfort) CG(N), Oeridian origin
Telchur (God of winter, the North wind, and cold) CN, Oeridian origin
Trithereon (God of individuality, liberty, and retribution) CG
Ulaa (Goddess of hills, mountains, and gemstones) LG, unknown origin
Wenta (Goddess of autumn, the West wind, and the harvest) CG, Oeridian origin
Xan Yae (Goddess of twilight, shadows, stealth, and mind over matter) N, Baklunish origin
Zilchus (God of power, prestige, influence, money, and business) LN
Zodal (God of mercy, hope, and benevolence) NG
The Flan pantheon can be said to be the most "generic" of the various pantheons described in the World of Greyhawk Fantasy Setting boxed set, as all of the Flannae deities are also listed as being "common". As the Flan people were assimilated and/or conquered by the invading Oeridians and Suloise, so too were their Gods and Goddesses brought into the invading culture. This is a process well known to history; the Romans were the masters of such syncreticism, and the Germanic tribes (down to the Norsemen of the Viking age) were not above bringing in foreign deities they found particularly attractive or useful.
The numbers: 36 deities total, 22 male and 14 female. 9 are lawful in some respect, 7 chaotic, and 29 neutral. 19 are good and only 5 are evil. This is in keeping with the numbers we've seen in the Suel and Oeridian pantheons, more or less.
What is interesting is the nature of the Gods of Flan origin. Four of them are Greater Gods, which is a record among "common" Gods originating in a particular race (the Oeridians have 2, the Suel and Baklunish have none). And the nature of those divinities is striking in its importance.
Beory is the "Oerth Mother". The very essence of the living world, encompassing all of nature and the life-giving rain. Nerull is the God of Death; the one universal constant that afflicts all mortal races. In the Gary Gygax "Gord the Rogue" novels, he is equated with the arch-daemon Anthraxus. Pelor is the quintessential "sun god"; another universal godly archetype. Only Rao, as God of peace, reason, and serenity, seems out of place in this quartet, but that might speak to the non-warlike nature of the Flannae, whom we are told were excellent hunters but poor warriors, and which led to their eventual downfall at the hands of the more aggressive Oeridians and Suloise.
This could indicate a certain level of respect, even on a subconscious level, for the Flan from the Oeridians and Suloise. Their deities are the Big Guns, and although the Suel have three Greater Gods themselves, none of them has been accepted by the rest of the populace in the Flanaess. Only the Flan Gods are "common". Folks just don't seem to like the Gods of the Suel.
It is somewhat interesting to note that Beory's position of Oerth Mother is bifurcated by both Ehlonna "of the forests" and Obad-hai. She is the Goddess of the forests, and He the God of nature itself. It might be suggested that they form a "divine pair"; the offspring of Beory, and in their way analogous to the various divine twins whom we see throughout European pre-Christian culture (Freya and FreyR amongst the most prominent examples).