thank you for your message. I'm sorry for the late response: I actually wanted to reply you earlier in the week, but it has been quite a busy one!
ACES framework allows custom look through the use of an LMT in the chain, which preferably should be applied on a ACES 2065 (LINEAR RGB with AP0) color space. Basically, after your ACES Proxy /CC conversion, you go back to ACES linear and apply a look that, for the very reason that it is applied to the widest ACES gamut with linear gamma, can then be applied to any other ACES output transformation. I'm sure that someone created some sort of film-emulation LUT as LMT, but I'm not sure where you can get them. Maybe Steve Shaw from Light Illusion can create you some if you want.
Anyway, you can try to use your LUTs in ACES, if you convert them for an ACES 2065 space. They will not necessarily work perfectly though, it depends on the LUT characteristics and, of course, their final aim. It will be better to create them from scratch, that's for sure.
If you want, I can try to convert one for you, so you can test it and let me know what you think.
Hope this helps,