In 2017, the new law declared multilingual education mandatory in Luxembourg where there are 65% of 4-year-old language minority children. To support 40 teachers with the new law requirement that asked teachers to use children’s home languages in the classroom, we offered a 6-month professional development course in translanguaging pedagogy that builds on children’s full linguistic repertoire. Mixed methods were used such as focus groups, questionnaires, and video observations. Through pre- and post-course focus groups we identified three groups of teachers: (1) those with mild monolingual stance who believed that the most important is to develop children’s school language, Luxembourgish, (2) those with mild translanguaging stance who expressed that children’s home languages are important but can hinder children’s Luxembourgish, and (3) those with true translanguaging stance who believed that children’s home languages are necessary for their well-being and development of Luxembourgish. The questionnaires showed that there was a significant increase in teachers’ positive attitudes towards children’s home languages and translanguaging. However, in the video observations we identified both positive and negative examples in teacher-designed activities that, when compared to the focus groups and questionnaires results, seemed paradoxical but portrayed a fuller picture of preschool teachers’ translanguaging stance in Luxembourg.