The only options to get FFB information I'm currently aware of (which doesn't necessarily mean much) is either using the DAMPlugin to record MoTeC telemetry and then review it later in MoTeC software like anyt other telemetry recorded using that plugin, or, if you want real-time monitoring, then using the shared memory plugin and something like SimHub (which is what I'm using) to visualize the data (excuse the awkward video, but I guess you get the idea):
In theory, any dashboard app using the shared memory plugin (most of them) should be able to access this data, but I'm not sure if any of them besides SimHub were updated to do so (as the addition of FFB data for the plugin is a fairly recent thing).
However, unless you run this on a second monitor or a phone (which I generally do) or something like that and want to use SimHub as an overlay, you have to run the game in either windowed or borderless windowed mode, which may or may not have some slight issues on your system (mostly either some microstuttering or a slight increase in input lag).
As far as I know, there's no other way to view FFB data in rF2 currently, as the options for plugins to write to screen are apparently very limited in DX11 and the old DX9 plugins don't work, as you've discovered yourself. Would be really great if the new UI that's been coming for quite some time included something like that or at least allowed the plugins to work again, but who knows if and when it will happen.