Goldenpoint I think the inconsistent racket feel is likely mental rather than equipment-related. With a technical issue, you'd probably pinpoint differences tweaking your gear or mechanics. But it sounds like this varies day to day even when those stay constant.
My guess is it ties to confidence fluctuations. When the racket feels good, you play free and easy without overthinking. When it feels off, you stress about technical things rather than focusing on your gameplan.
My advice - when struggling with racket feel, don't spiral about technique. Instead build momentum stroke-by-stroke, rallying patiently until you find your rhythm and openings to attack. Stay present in each point rather than questioning your tools or fundamentals. Overthinking causes more inconsistency than any racket specs.