Multisource application with cross source reference of shortSha

[FlipflopMan]

Im trying to setup multisource application where one source targets helm registry, second source provides short sha of current commit.
In theory there is option to pass via helm parameters ARGOCD_APP_REVISION_SHORT_8 variable, hoiwever this variable only is applied to source where we set reference.

Have anyone tackled such setup? We already trick argocd by umbrella chart commited to source repository, however this setup adds additional complexity(nested config from stub umbrella chart + chart version hardcoded in code repository)