> Our knowledge about the sexual transmission of mitochondria and plastids (hereafter organelles) in isogamous eukaryotes comes mostly from studies of the yeast Saccharomyces cerevisiae and the green alga Chlamydomonas reinhardtii which are both unicellular species. To investigate organelle inheritance in a multicellular organism with morphological isogamy, we studied the filamentous brown alga Ectocarpus siliculosus, in which each gamete contributes one plastid and at least one mitochondrion to the zygote. ...
* 2004 - Inheritance of organelles in artificial hybrids of the isogamous multicellular chromist alga Ectocarpus siliculosus (Phaeophyceae)
So it is possible, but it seems like very rare.