OMAD is simplest, 5:2 can get tedious to keep track of.
Calorie counting, not such an issue, if you eat less you burn less so that doesn’t really help. Whats more effective than counting calories is to just hit that one meal a day with focus and consistency each day.
Omad, it works. It will do the thing you need done. But instead of putting in the work at the gym, its a mental and spiritual workout to be that disciplined.
You may be grumpy and a tad aggressive on omad, so you have to allow yourself that margin, but yeah omad works 100%
Don’t over think it.
Just find a schedule for you that works and follow as much as possible.
If taking the weekend off makes sense do it. You will find not eating for 8 waking hours is not that tough, (or for Omad only having a meal a day) and it becomes a routine.
Also when you need to break the fast because of special occasions (weddings, family brunch, vacations) Give yourself permission to do so.
Good luck!!