Am always on the A351 from either LHR or CDG, so late afternoon.

2.5h should be fine. But, if there’s even a short delay at departure (say 1 hour), you’ll likely misconnect. The immigration plus baggage wait can be 1.5h or more on a bad day.

JAL should rebook you though. I assume same day rebooking wouldn’t be an issue as HND-KIX no doubt has lots of flights each day. The problem comes when your connecting flight is to a smaller airport that has one or two flights a day. The inevitable misconnect means you stay the night at HND.

What JAL won’t do is have ground staff usher you past the lines. Maybe you can shove your way through yourself and cut the queue, but I’ve asked many times flying F, as OWE, where I knew I would definitely misconnect, and always been told that it was “difficult” (with the usual Japanese politeness).