Hello
I'm not sure that I've understood the meaning of online/offline. If you mean by online that the simulation of mangrove dispersal is done in the same time than hydrodynamics, the answer is yes. Moreover, there is no offline version.
If you assume that your particles behave like algae, you can use full options of the algae transport of Telemac-2D. Numerical options and input/output data are described in the newly released
user manual. If you want more details about theory and numerical options see the following
report
with my best regards
Riadh