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Non-Abelian gauge fields are versatile tools for synthesizing topological phenomena but have so far been mostly studied in Hermitian systems, where gauge flux has to be defined from a closed loop in order for gauge fields, whether Abelian or non-Abelian, to become physically meaningful.

We show that this condition can be relaxed in non-Hermitian systems by proposing and studying a generalized Hatano--Nelson model with imbalanced non-Abelian hopping. Despite lacking gauge flux in one dimension, non-Abelian gauge fields create rich non-Hermitian topological consequences.

Under only nearest-neighbor coupling, non-Abelian gauge fields enable Hopf-link bulk braiding topology, whose phase transition accompanies the emergence of exceptional points (EPs).

At both ends of an open chain, non-Abelian gauge fields lead to the simultaneous presence of non-Hermitian skin modes, whose population can be effectively tuned.

Asymptotic analysis shows that this tuning mechanism stems from the interplay between the Abelian Hatano--Nelson coupling and effective high-order hopping, which becomes substantial near the EP phase transition condition. 

The predicted non-Hermitian phenomena, enabled by non-Abelian gauge fields, could be realized in synthetic dimensional optical platforms such as time-multiplexed photonic mesh lattices and driven ring resonators.