I agree with not keeping a growing dog, or any dog, in a crate all day. Can you try pens or a gated room? You'd need two pens or rooms of course. At least they could move around a bit more. I imagine you will need very sturdy pens.
Other options other folks use is doggy day care, a friend to come in and walk them and at least let them out in the yard for a bit, or a professional dog walker.
Are they siblings? Regardless, at the same young age they are they should be doing things separately so they do not bond too closely to each other and not to you. One goes to DDC one day and the other the next day? As well as pens or gates? They should be going to separate dog classes too, accordings to other sibling puppy wisdom I've read.