Translation:Can you come this weekend?
They are not interchangeable here.
这个周末你们要来吗？ can mean
Do you want to come this weekend ?
Will you come this weekend ?
depending on the context.
I think they were trying to emphasize that it was a plural "you," which English doesn't have (like vous, voi, or ustedes)
If one of the drop-down hints was "will," how is one to know that it's not "Will you come this weekend?"
"you guys" is not correct English and should be used as substitute for plural 'You'