Eeehhhhh..... I'm very much on the fence here... I think I would personally be disinclined to do the trade, at least right now.
-Kittle is banged up and Reed is playing well. There is little reason for the 49ers to rush him back. I guess it seems like he'll be back next week, but then that means if you do hold another week then you'll at least be able to start him right away once you get him
-Engram is running routes on 100% of team pass plays - he hasn't found the end zone yet, but better days have to be ahead for him if he's running routes that often, and now that Barkley and Shepherd are out
-Replacement value of TEs on the wire seems fairly high this year (of course depends on the depth of your league) whereas we all know replacement value of RBs is low
BUT the reason I'm on the fence is as Farhad pointed out, your RBs DO have clear handcuffs, and not only that, handcuffs that are good and would be expected to likely take over the majority of the work instead of being in a messy timeshare. So if you have room to cuff your backs then there is less risk in letting go of Robinson. But at the same time, I'm not sure I'd want to be spending 3 roster spots on cuffs, which is why if I were managing the roster, I'd probably rather keep the RB depth with Robinson.
Sorry that was probably clear as mud!
I'm a dudette.