Ahem, per Canon 1024, any baptised Catholic male may be elected Pope. Priesthood is not a requirement, nor a barrier.
Second, as the election is for the Bishop of Rome (Latin Rite), whether Orthodox prelates would have a vote or not is a big depends. It would depend on how the Orthodox were folded back into the Church.
Currently, I believe only Latin Rite members vote. The patriarchs of the Melkite, Chalcedonean, Syro-Malabar and other Catholic churches don’t help select the Bishop of Rome. Likely this model would be followed and Orthodox prelates would not have a vote.
However, were the Orthodox made part and parcel of the Latin Church, then the Orthodox prelates would likely have a vote.
As the Orthodox came not out of Rome, but out of the Eastern Catholic Churchs, I suspect that the Orthodox will be blended back into their respective Catholic Churches. For example, Greek Orthodox might merge into the Melkite Catholic Church. That’s purely my speculations.
God bless one and all…