You will have oil there at the output shaft.
All those parts, gears, etc... inside that intermediate housing need lubrication. That's why the shaft seal and the o-ring.
Yes, the oil you have circled is what the o-ring is supposed to keep out of the clutch basket. The o-ring is supposed to keep the oil from leaking thru the splines.
Actually, if you look at your oil sight glass, if you get oil filled above the centerline of the glass, it will be right at the lip of the seal there in your picture.
I made that mistake when I did my clutch a couple of years ago. Had my sight glass over 3/4 full, pulled the basket out and out came the oil till it drained down level with the seal. Then even more came out as I replaced the seal......