Both digimon are in fact an antithesis toward each other among their rank in Royal Knight Squad ( If IMP is considered as Royal Knight or Ex-Royal Knight. )
Let's state some antithesis point I mentioned above:
1. Alphamon Ouryuken is a Royal Knight Digimon whose weapon is composed of Royal Dragon Digimon ( Ouryumon can be roughly translated as Imperialdramon in english ), and Imperialdramon Paladin Mode is a Royal Dragon Digimon whose weapon is composed of Royal Knight Digimon ( Omnimon/Omegamon ).
2. Due to above, it's safe to say that these 2 are the strongest wielder of their own Inforce ability. Alpha InForce for Alphamon Ouryuken, Omega InForce For Imperialdramon Paladin Mode.
3. Colour-wise, nuff said.
4. Position and rank wise, Founder ( IMP is rumoured to the one who assembled the RK during or after digital world crisis ), Controller ( Alphamon is stated to control, help, even fight the RK during digital world crisis if the said RK are entered a strong civil war).
Okay enough of my rambling here, here's my analysis toward this fight:
1. Given all member of RK are capable to fight each other equally in a fight, it's safe to assume that RK are somewhat hax resistance toward their peer haxed ability (Jesmon, Gallantmon/Dukemon, Magnamon.), so when it comes down to fight, the one with high raw combat power will have a higher advantage in a fight.
2. Alpha Inforce vs Omega Inforce are basically synonym comparison of Immovable Object ( All attack can't reach the Omega InForce User ) vs Unstoppable Force ( All attack can't dodge from Alpha InForce User).
So the conclusion is the match will likely end up a Draw. But if I m forced to take a side, I will lean on IPM to win the fight.