You could add a good quality "programmable overcurrent protection switch" (see amazon.com - about $20), but that means fiddling with the cables, which must be done properly. Moreover, I would buy a good quality one (no cheap Alibaba stuff or so), otherwise you add risk to risk.
As for the problem of avoiding overcharging, here is what I do:
1) discharge the battery once (to 5-10%), then monitor the charge every 15-30 minutes to make a "time vs. charge %" graph.
2) buy a remote switch ($10 or so). I use a TP-LINK Tapo P100.
3) Connect it to an app like SmartThings that allows you to easily turn it off automatically after a certain time interval. So I can turn it ON whenever I like, and then program the switch to turn off the charger when the battery is at 80% according to the graph in (1).
It looks a bit complicated, but it works well and doesn't cost too much. And after some time you know more or less by memory how much time you need. And it works even when you are not at home.