1) does bridges like obfs4 work properly within latest whonix?
Yes. For obfs4, wait for Whonix 11. [Release announcement most likely later today.]
2) is it just like configuring normally within the tbb?
No, unfortunately not.
Bridges in Whonix have to be configured on Whonix-Gateway. Manually. Using /etc/tor/torrc. Not using TBB.
is it true bridges are more vulnerable to attacks and user profiling than normal entry guards?
A general Tor question. Please see this discussion (linked from Whonix https://www.whonix.org/wiki/Bridges documentation) but copied here for your convenience: