According to this chart, the Ethereum blockchain is busiest from 1 PM UTC to about 6 PM UTC average.
https://cointelegraph.com/news/here-are-the-best-and-worst-times-of-the-day-to-use-ethereum
This was just according to your opinion only, chart is just a guideline but not an assurance for us to get a nice profit.
Aside from that I am just using chart depending in the exchange that I've used every I made an activity in terms of day trading
in cryptocurrency. In short, I am not depending all my analysis in the chart only, that's it!