1. For Nekhbet breaker you usually can combo into it from a move that ground bounces. You can usually combo into it after chaos banish.
2. Tympani drive is a weird one for big band. For lighter characters you can do launcher into tympani drive, but to be more more consistent with other characters the best way to link into it is after a super sonic jazz.
3. Lock n Load and Pummel Horse are both pretty slow, and for these reasons it's pretty hard to combo into. For some characters you can do launcher into lock n load and pummel horse, but a more consistent link would be to combo into it after dash attack 2. For example, you could do merry go rilla->dash attack 1 and 2-> lock n load and pummel horse (pummel horse you might have to time it for it to connect).
4. Flesh step. Honestly idk about this one. In the original game it was a teleport and a movement option, but in this game since you can't move behind your opponent the move's pretty useless. Don't use imo, no real use for it as far as I can tell.
5. Omnonom. Same thing will lock n load and pummel horse, pretty slow and hard to connect with. I think it's better to press the head games button and then the blockbuster as that seems to be a faster option. Sometimes you can get it to connect after a wall bounce from dash attack 2, but i dont think it's consistent with all characters. The best way to use it imo is to use it as a call out option, whether you think the opponent is going to dash or you are already headless and are in a position where it would connect.
6. Lonesome Lenny and Boxcar George. Lonesome lenny is a pretty broken move, broken in the sense in that it doesn't work properly. The HP of loneseome lenny doesn't scale with the peacock's attack stat, meaning the amount of hits needed for it to explode depends on the attack stat of the peacock. From what I've seen, the best way to connect it is to put it down, do dash attack 1 and 2, then immediately use bandwagon rushdown so you don't get hit from the explosion.
7. Magnetic Trap. Ok honestly this one is pretty easy to combo into. All you need to know is that it connects with airborne opponents. So basically, whenever your opponent is off the ground, you can use it. A simple way to use it is to dash attack 1 and 2, then use magnetic trap.
Hopefully this helped you out. If anyone else has other suggestions, feel free to addon.