How old is this house?
Simple solution would be to drill through both joists and insert a 1/2" carraige bolt. Put a few 5/8" washers on each end and tighten the bolts. Make the hole the bolts are in a little oversized to compensate for the beam distortion. Tighten the bolts over a week or two to cinch the joists together. Then install some blocking to stabilize the connection.
Ron

Are they cupping or tilting. Cupping is from wet wood drying out. I doubt they will cup any further.
I would simply install 2x of matching width tight between them.

Thanks folks:

This portion of the house was built in 1969. There is only one joist at the very end of the house that I would consider having a slight tilt, all other 2x10s look square along the entire span except right at the ends over the main beam.

The current state of the joists look to have been in this position for years since there was a major kithcen renovation 10 years ago that worked around the floor uneveness at the center line of the house but I wanted to make sure this didn't get worse.

Thanks for the ideas!

You could use one of the screw-type car jacks (not a hydraulic one, you can't use them sideways) to put a bit of pressure on to tilt them back the right way, then measure and fit your blocking. It'll have a bit of bite that way.

If you cut solid blocking the right final size and bevel one end you can drive it into place with a block of wood and a big framing hammer.