Let’s say, if a Brahmin was present at the battlefield, Dharma would remain the same for Arjuna and that Brahmin: Dharma is to fight Duryodhana because Duryodhana is representing adharma. But swadharma will be different: Arjuna’s swadharma will be to fight Duryodhana like a warrior, and the Brahmin’s swadharma will be to fight Duryodhana like a scholar.