yes but also the steelers can't even trade him until after he signs his franchise tag. right now he is not technically on the steelers. they have his rights but he is not under contract with them, hence they cannot trade him until he signs the tag because you can't trade someone who isn't under contract.
so the idea of trading him is very tricky. they need Bell to play ball and sign his tender, they need another team to play ball, and they (the Steelers) need to want it too (I think they would rather have Bell for the postseason run and get a 3rd round comp pick than get something marginally better back in a trade since they have serious super bowl aspirations). the teams you mentioned, though, are some of the teams that have the cap space to take him on. I believe there are 7 teams with 14.5 million or more in cap space. just for fun let's go down the list:
Browns - i doubt they would take him since they signed Hyde, have Duke Johnson, and drafted Chubb in the 2nd round.
Colts - I could see them wanting him (and they have 49 million in cap space)
49ers - I could see them wanting him (and they have 40 million in cap space)
Texans - They have Lamar Miller but I could still see it (27 mil in space, maybe they include Miller in the trade)
Titans - doubt it, not with Dion Lewis and Derrick Henry
Jets - doubt it, they have Crowell and Powell and also aren't a contender
Raiders - doubt it, they have Lynch and also only have 15 mil in cap space so this would use most of it. They seem to also be cash strapped in general.
So yea, I think the possibilities would be Colts, Niners and Texans in the remote possibility he gets moved. Man imagine him on the Texans? Watson, Hopkins, Fuller and Bell, whew.