Xu 需: hesitate, wait and see (觀望). Some translators translate it as ‘to want, to need’ (需要) but this meaning is relatively young (starting with Northern Qi dynasty (550-577) ).
About guang heng 光亨 see here.
She 涉: to cross a river.
Da chuan 大川: a great river, probably referring to the Yellow River. In the Zhuangzi we read:
Feng Yi got It, and by It swam in the Great River…
In the Soushenji 搜神記 it is said that Feng Yi drowned in the Yellow River:
In the times of the Sung state, Feng Yi of Hung-nung Commandery was a man from the head of the levee in the T’ung district at Hua-yin. On the first keng day of the eight month, he crossed the Yellow River and was drowned. The lord of heaven made him the Ho-po (Lord of Rivers). The Wu-hsing Shu says: “Ho-po died on the day keng-ch’en. On this day it is not propitious to take boats on long journeys for one may drown and never return.
(DeWoskin & Crump (tr.), In Search of the Supernatural, p. 45)
There is blessing and protection.
Glorious accepted offering.
The divination will be auspicious.
Advantageous to cross the great river.