I think that so6p from the beginning only had byakugan and powerful sealing techniques.With the powerful sealing techniques he defeated juubi abd sealed it in his stomach.when he sealed it in him he acquired sharingan and rinnegan.With the power of sharingan and rinnegan he get the power to creation.In japanese myths juubi is monster which create thing or world and destroy it .It has no other feelings.Rikkudou created uchiha and senju .Two boys. rikkudous sennin gave sharingan rinnegan to one boy that was uchiha and give his body power to second boy was senju.
Rikkudou passed his power ful sealing powers to a clan, uzumaki clan.
Byakugan and sealing power combined
just like said rikkudou in the beginnin only posessed ninjatechniques ,byakugan and sealing powers. WE know that hyuunga clan good at hand to hand compact .Rikkudou sennin with the byakuga can see the enemys and by touching them and he can use sealing powers.