
about all i can tell you here is that this was a Shingon temple in Miyajima, can't remember the name though
Since you mention Shingon, probably Kobo Daishi/Kukai? Is there a vajra in his right hand?
Normally rupas depicting him carrying a vajra whilst seated but the amount of wrist malas on the statue's hand in the photo is obscuring...

this fella was stood outside Kokura castle, next to Jizo and a small Inari shrine
Looks like Batō Kannon 馬頭觀音 Hayagriva Vidyaraja or Hayagriva Avalokitesvara or Horse Head Avalokitesvara (notice the horse head/face on top of the statue head)

Sofukuji temple, Nagasaki
Ah! the central statue is the familiar and famed Dharma Protector Skanda Bodhisattva (J: 韋駄天 Idaten or Ch: 韋馱 Wéi Tuó) honoured mostly in East Asian Mahayana Traditions. He is mentioned in the Golden Light Sutra and a brief mention of his name as Sanankumara (Skt: Sanatkumara) in Maha Samaya Sutta. Also popular in Saivaite Hinduism as a youthful warrior son of Shiva and ascetic practices, in South India, especially amongst the Tamils. No idea on the other statues other than an obvious statue of Hotei?

Avalokitesvara Bodhisattva with Sudhana (Good Wealth) and the Dragon Girl (Nagakumari?)