It is a passive unit so it could work as a splitter of a buffered signal well enough, but there could be issues with the passive mixing. As long as all your mixed signals are buffered and have approximately the same output impedance it should
be fine, but you'd be better off with more predictable results from an active mixer.
I have never used this product
, but it is unique as far as I can tell, and fits your needs (depending on your attitude towards Behringer).