Identical twins, of which they are the 4th pair in the NHL, but I believe they would be the first pair to the HHOF.
It isn't just about the numbers but the uniqueness and greatness in their careers together. They were drafted by Burke 2 and 3 in 1999 and played nearly 2 decades for the Canucks. While they were stars in the NHL; they are also legends in Sweden, winning Olympic and World Championship gold for their home nation.
Let's do the hockey version of the Keltner Test: the Hall of Fame Quiz.
1. Was he ever commonly thought of as the best player in hockey while he played?
Daniel - no
Henrik - no
2. Was he ever commonly thought of as the best player at his position while he played?
They each had a peak year where they were as good as anybody in hockey, but I don't think it would be fair to say that they were commonly thought of as the best LW and C during their careers.
Daniel - no
3. Was he ever among the top 10 leaders in any key stats? (G, A, Pts, W, SO, etc)
Daniel - Yes. He had top 10 finishes in Goals (2011), Assists (2011, 2015), and Points (2011, 2015)
Henrik - Yes. Had top 10 finishes in Assists (2007 to 2013 as well as 2015), and Points (2010 thru 2012 as well was 2015).
4. Did the player ever lead the league in any key stats? (G, A, Pts, W, SO, etc)
Daniel - No 
Henrik - Yes, he led the league in Assists (2010 thru 2012) and led the league in Points in 2010. 
5. Did he ever have an impact on a deep playoff run?
Both brothers were key players for the Canucks Finals appearance against the Bruins in 2011.
6. Was he a key member of a Stanley Cup winner?
7. Was he ever a team Captain?
Daniel - No. 
Henrik- Yes, he was Captain from 2011 until his career ended in 2018. 
8. Was he ever team Captain of a Stanley Cup winner?
Neither did this.
9. Did many regard him to be an excellent defensive player?
Neither of the twins were feared, but both played typically Swedish hockey, with an awareness of marking opponents and mind the fact that there are two nets on the ice. Both received Selke votes over the course of their careers. I think that's a fair 'yes'.
10. Did many regard his physical play/hitting to be an intimidating factor? (NOTE: We're not looking for pests here)
11. Did he play a lot/well after he passed his prime?
At the age of 37, the Sedins continue to be durable and are even providing top 6 offense. The number of shifts where they dominate is much less, but they played well even when old.
12. Was he ever elected to the 1st or 2nd All-Star team?
Daniel - 1st All-Star in 2011, and 2nd team in 2010. 
Henrik - 1st All-Star in 2010 and 2011. 
13. Are many any other players with similar statistics in the HHOF?
Daniel - of the most statistically similar players who qualify for HHOF induction, all are members. 
Henrik - of the most statistically similar players who qualify for HHOF induction, all but one (Peter Bondra) are in the Hall. 
14. Did he win a Hart, Lindsay, Norris or Vezina Trophy? (NOTE for goalies: prior to 1982, use 1st All-Star selections)
Daniel - won the Lindsay in 2011 
Henrik - won the Hart in 2010 
15. Did he win a Conn Smythe Trophy? (pre-1965: see resources)
Neither won a Conn Smythe.
16. Is there any evidence to suggest (due to circumstances beyond his control) that he was significantly better than is indicated by his statistics? (NOTE: We're looking for things like time missed due to global conflict, world politics, league wars, etc... NOT INJURY!)
I don't see how either would qualify for a point under this section.
17. Did the player bring bring positive and intense focus on the game of hockey?
This is the Gretzky/Ruth/Ali point, and one which is exceptionally difficult to score. I don't see it.
18. Was the player innovative, inspire a new style of play, or cause the league to change any of its rules as a result of the way he played?
Think of Jacques Plante changing how goaltenders play the puck, or how Wayne Gretzky re-wrote our concept of controlling the puck behind the net... I think the twins should qualify for a point due to how they changed the PP (and even some ES situations) league-wide with "The Sedin Tip".
My own cut-offs run something like:
13+ = the best of the best
11-12 = among the very greatest who have ever put on skates
9-10 = great player
5-8 = clear Hall of Famer
4 = borderline
3 = weak argument
1-2 = completely unqualified
As far as I see it, the Sedin brothers are clear Hall of Famers. Looking back, the only thing they weren't able to do was win a Stanley Cup, and they came so damned close it's not even funny.
Remember, the point of the test is to ask if the player in question is HOF calibre, not to peg down his exact value. Question 16 is better asked of players like Igor Larionov, for example, who missed about a decade out of his NHL career due to global politics. There is a reasonable argument to make that he was better than his statistics suggest. The Sedins? We're nibbling at the margins.
All-time NHL Goals Per Game: 3.03
GPG during the Sedins careers: 2.78
It's not so much that the twins were punished by the era in which they played, which approached historical average, but that players during the 80s and early 90s played in an era of exaggerated offense.
Even then, keep in mind that the test isn't using non-era adjusted career G, A, Pts as part of its package, something I purposely did so that we don't run into these issues when comparing players who may have played in different periods of time. The only place we could have run into trouble was the question which asks if players with similar stats are in the HHOF. For years, I had my own sheets normalized player stats and compared how statistically players were, but this had shortcomings.
-I was the only person with access to these numbers, which greatly limited the ability of other people to answer the question in a productive or easy way.
-It was one hell of a lot of damned work.
So, now I direct people to view the player's page at hockey-reference.com, because all of that is taken care of there. It simply removes the vast majority of the hassle which comes with comparing players across era.
What I'm spending a long time saying is that I don't think a strong argument can be made that the Sedins were significantly better than their stats suggest, as their numbers already indicate that they were elite players and point us in the direction of viewing them as being Hall of Fame calibre.