The audio has a glitch: it sounds like five syllables instead of four (counting ea as two) I.e. it sounds like "qui es est ea".
Please report errors with the "Report" button and not in the sentence discussion. Thank you!
I = ego You = tu He = ille (or 'is' or 'hic) She = illa (or 'ea' or 'haec') It = illud, id, hoc We = nos You = vos They = illi (or 'ii' or 'hi')
Ego, tu, is/ea/id, nos, vos, ii/eae/ea. But you can leave them out since the verb holds all information.
Yes, as all languages with declination the word order is interchangeable. There is of course the normal ordering which I think is actually the one tou propose.