Mainly ABAB Quatrains with No Clear Meter
When it comes to the form and meter of this poem, Pound is very clever at walking a tightrope between the old and new. On the one hand, he's happy to use classical four-line stanzas, or quatrains, and he also uses a traditional ABAB rhyme scheme (where each letter represents the end rhyme sound for that line), like the kind you see in his opening stanza:
For three years, out of key with his time,
He strove to resuscitate the dead art
Of poetry; to maintain 'the sublime'
In the old sense. Wrong from the start—
But for all of this homage to classic poetry, Pound has no time for any sort of meter in each line of his poem. This makes sense, since the guy would go on to say that poetry should be written "in the sequence of the musical phrase, not in sequence of a metronome." In other words, Pound wasn't a fan of lines that go, "I went outside and watched the bird," like a beating drum. He wanted his lines to be written the way people actually talk, like you get with, "For three years, out of key with his time,/ He strove to resuscitate the dead art." But he still wanted to give props to classic art with his rhyme scheme and four-line stanzas.
You can definitely see Pound's use of form as an homage to the past, and his meter as a way of injecting something modern into something old. It's almost like sucking the jelly out of a classic donut and refilling the thing with something modern like… uh… Jello pudding. You get the idea: tasty, yet comforting.