This is the first time I’ve seen this one. Best result I saw from 30 seconds of googling:

In 2020, the National Runaway Safeline (NRS) began using LGBTQIA2S+ to recognize those who identify as “Two-Spirit.” This phrase refers to people who identify as having both a masculine and feminine spirit, and is used by some Indigenous and Native communities.

“Two-Spirit” describes the cultural-specific understanding for the diverse gender traditions of Indigenous and Native people. Historically, Two-Spirit people were among the most respected in their communities, often serving as community healers, ceremonial leaders or caregivers to the elderly or orphaned children. This is consistent across many cultures who experienced extreme oppression and intergenerational trauma through periods of colonization. Today, young people who identify as Two-Spirit may suffer from inequalities perpetuated by a legacy of discriminatory laws and policies.
Source: National Runaway Safeline