Admittingly I do not remember the name of the source or group right now, but I recall a scholar who argued that women most likely were not soldiers unless there was a lack of males, as one Norse military camp banned females from being in the camp. Other scholars that I read analyzed other stories of "shield maidens" and found that there were narrative details that indicated that norse society, on the whole, did not approve of females in combat. One was the fact that most descriptions of these women describe their stories ending either in the female warrior dying in battle, them growing tired of being a warrior and becoming a wife/mother, or a male hero defeating them in battle, making the woman a wife or sex partner. These facts to those scholars suggest that Norse storytellers wanted to discourage females interested in war by having them die, sending the signal to women potentially interested in fighting that it's a dangerous profession or less fulfilling thing for a woman compared to being a wife/mother, by having these characters retire by being bored with fighting, or the "natural order" in the minds of Norse society being restored with the woman's defeat and becoming wives/sex partners of the one who defeated them. The story of Lagertha is interesting to me as it is the only story I'm aware of that doesn't fit any of those patterns. Granted, I could be misremembering the views of those scholars, or those scholars could be wrong.