The rise and fall times are little different, there is one faster than the other turning on and off
This will not affect on switching time between the high and low mosfets?
I would like also if you can explain this issue of adjusting the timing for the mosfets " on and off time " with the pulse duration from the sg3525 ic
You surely should not replace individual transistors in parallel circuit. Different timing of HS and LS switches can but must not necessarily be a problem. If I perform the replacement in a redesign, I'd schedule a complete set of characterizing measurements and possibly adjust circuit parameters. In repair service, it's more trial and error. According to datasheet there's a good chance that it work flawlessly.