All's I fish are grass lakes. Well...they have rock, boat docks and wood in them too, but grass is the predominate cover.
The deepest grass will stay green and healthy until well after I quit fishing in a few weeks, and usually even after ice up if the water is clear, the ice is good clear "black ice", and we don't get a ton of snow on the ice to block sun light.
Late fall to me (and the bass here) is when the water drops into the low 50s to mid 40's...below that it's early winter.
Assuming your asking about largemouth in late fall (smallmouth are a whole other topic), they get quite fickle in late fall BUT predictable. There's going to be a few around shallow hard cover in grass lakes, like docks, wood, rock, etc....but since by now the bulk of the shallow grass (less than 6 feet) has died or is turning brown and dying back seemingly by leaps and bounds every day, they are not using it much. If you want to beat the bank in a grass lake in late fall, hard cover is the way to go....jigs, t-rigs, spinnerbaits, squarebills....all the stuff you would use year round is still in play. But your going to grind for bites up there. It's one here, one there...there's not going to be bunches of them up there like there are spring through mid fall. The reward is, however, they are often big fish. Some of my biggest largemouth of the fall are caught in the dirt on hard cover in cooler water.
The other half to this equation is the healthy deep grass. Coontail seems to hold them BETTER than milfoil during this time, but there will be places where milfoil is still holding them, you just have to fish both and see what's going on that given day. The BEST spots will be....the best spots they were in all summer. If you have miles and miles of green healthy deep grass in the fall, just like the summer, they will be in the areas with rock/bottom changes/points, turns/bends/etc...in the grass.
The "myth" of northern largemouth being more aggressive in cold water than their Florida strain cousins gets turned on it's ear a little here. Your going to work to catch them when they get out on that deep grass late. Partly because they are a little more lethargic (not nearly as bad a Florida's) but mainly because that deep grass is also a haven for the entire eco-system. Bait is abundant and, and the windows to catch them grow smaller each passing week we get closer to winter. This is NOT the time to try to power fish them....if I want to power fish this time of year, I go chasing smallmouth or looking for the big loaner largemouth on the bank. These deeper grass largemouth in my 25 years of chasing them in late fall require a little more finesse. Sure there might be really really tight windows where they get aggressive but they are few and far between and can't be counted on. Now is the time I turn to a heavy (to make sure I get it into the grass) BUT extremely compact offering. You'll rarely tempt the bigger ones to leave the comfort of the grass for dainty stuff on light line, so your weightless senkos, ned rigs, light drop shots, and other finesse stuff that works spring - mid fall is not the best bet. I'll use a the lightest t-rig I can get through the grass with (sometimes 1/4 oz, sometimes 3/8's, but often 1/2 oz.). They really really seem to pump the breaks on me trying to bomb in there with a 3/4 or 1 oz weighted offering, so I don't bother. If I have to wiggle and jiggle a 1/2 oz weighted bait to get in there, then so be it, it gets more bites. Your going to want to put the baits away with big flappy arms/legs/claws...this is the time for NO action, and the more compact the better. Something along the lines of a beaver style bait, a tube, a compact craw with no obnoxious claw action, and even a senko style bait on a weighted t-rig are king this time of year. IF they are biting plastics good OR if you are just looking for a few big bites, a compact 1/2 oz flipping jig with a dead action trailer is a good 1-2 punch to t-rig. I use the t-rig to find them, and the jig to get a big one. Starting with a jig has always been risky business for me...there's days they seemingly DON'T want it yet you'll get plenty of bites on soft plastics. Some will say the opposite and tell you to just lock a jig in your hand and get to work, I'm just telling you what's worked for me for a long time.