Jagr owns Ovechkin in every possible way in both regular season & playoffs, whether its individual stats or team success/titles. Jagr owns Ovechkin in international team wins as well.
A good argument for OV over Jagr starts with All-star team finishes
Jagr 7x 1st, 1x 2nd
OV 8x 1st, 4x 2nd, 3x 3rd
Their best three seasons are similar (Jagr has way more points, Ovechkin has way more goals), but there is no doubt that if one looks at their best 5 or best 7 seasons, Jagr is ahead of Ovechkin.
The issue is, Jagr has little outside of his best 8 seasons. Ovechkin has been in the talk for the best LW pretty much every season (well, probably this season injuries finally slowed him down, but that's his 16th season already). In this regard, Ovechkin is like Bourque, who was top5 in Norris voting almost his whole career, and that brings Bourque ahead of defensemen with probably higher peak. Ovechkin is doing a similar thing on LW.
Let me also do the comparison for the three best consecutive seasons.
In 2007-2010, OV led #10 in points by an average of 27% and led #10 in goals by an average of 50%.
In 1998-2001, Jagr led #10 in points by an average of 33% and led #10 in goals by an average of 20%.
Let's transform it in the 2018/19 (last full season) currency: in 2018/19, #10 in points was at 96 points, #10 in goals was 41 goals.
Peak Ovechkin projects into 41*1.5=60 goal, 96*1.27=122 point guy, peak Jagr - into 41*1.2=48 goal, 96*1.33=128 point guy.
This is very, very close, and I would actually take the 60-goal guy.