Puzzle is not an obvious frequentative, if one at all. EOL suggests a possible derivation of an Old French acception of poser meaning to take something upon which there is not agreement as a given for now (se dit en parlant de certaines choses dont on ne demeure pas d'accord), leading to English ‘to pose’, "to put questions to, interrogate closely" (ca.1520) and thence to puzzle, confuse, perplex" (ca.1590). Weekly suggests an apheresis of ME opposal, opposaylle (Lydgate ca±1425), for 'interrogation', presumably from French oposer (1176) for 'to object'. There seems to be a possible development of French oposer to opposer (<1500), 'express objection to', along with a possible conflation of Old French pauser, to rest, from Latin pausare to stop, cease, and thus morphing into a status of perplexity or bewilderment in 16th-C English pusle, puzzell.
Uncertain.