I know about
glmmLasso but would prefer to use elastic net. I wonder if there are any glmm analogues of
glmnet out there, or if anyone is working on any. I couldn't find any in my searches. Thanks
Maybe look at the MMS package. The lassop function seems to only be for lasso analysis, yet is clearly built on the glmnet package and includes some of its parameters such as alpha. If nothing else it is likely a good package to modify for your purposes.