This -(i)er alternative of trace3 is found only in the Bibbesworth manuscript tradition and seems to be without any etymological grounds.
s.
1agriculturaltraces, pair of ropes, chains or straps by which a harnessed draught animal pulls its load:
(
c.1290; MS: s.xv1
) le traiser (var.
(5: s.xiv1/4) tracer;
(B: s.xv1) traicier;
(C: s.xivin) traycer
)(M.E. traishors) ad la brascerole (M.E. traishose or the nesill)(O) 344va
(
s.xvin; MS: s.xv1
) Le traser od le braserole (M.E. þe trays wyþ þe brasyng eye)66.9
tracer2 (c.1290)