First complete the omitted words and change them into normal word order:
If curse could be the verse that tends to make one worthy man my foe, how well it should flow so ever .
It can be seen that this poem uses the subjunctive mood, and its grammatical structure is as follows:
[Conditional adverbial] If curse could be the verse that… (If curse could also be the verse that…) )
[Attributive clause] that tends to make one worthy man my foe (a poem that intentionally turns a respected person into my enemy)
[Main clause] how well it should flow so ever How has it been passed down by word of mouth for so long?
The following is an alternative translation based on the rhythm of the poem:
[Five-Character Poetry]
Curse is not poetry
A noble person turns into an enemy
If there is no reason
How can you be the best in the world?
[Modern Poetry]
Who said that no one cares if a curse becomes a poem?
Even if a noble person writes a poem and is cursed