Interesting-I was fishing with a mate many years ago and there was a full eclipse of the sun sometime during the day. We often fished this spot and there are a lot of flocks of birds about, crows, seagulls, starlings etc. All these birds thought it was night time and started flocking and flying to their roosting places. It was very noticeable the change in their behavior. They looked very confused when it started to get light again. It was quite amusing. It was like they did not know what to do next.
I imagine fish must think the same and whatever it is they do at dusk they will start doing it during the eclipse. How this will affect your fishing, really dunno but, fish that tend to come on late in the day at dusk time might do so during the eclipse, roach come to mind maybe.
Although if I remember rightly we did not catch anything during the eclipse but, that's no sausage as we did not catch anything much full stop, it would take more than a eclipse to change that, a bloody miracle maybe.! God almighty riding a chariot of fire across the face of the sun might be a better sign of my fortunes changing.