No they wouldn't, the bonus would be locked behind t4
Yes they would.
Check repair speeds pls.
Even if that were true why would it be a problem? The WFA engineers have plenty of other advantages, and their factions have better repairs already
Because EFA would get more by investing less. EFA armies where given buff with sweeper repair speed bonus they simply do not need more.
PLS try to keep your comments specific "their factions have better repairs already" does not really say much.