A great read as an introduction to emotional speech is Marc Schröder's first chapters of his dissertation which is available online at the university of Saarland
Since version 0.29.1 there is the possibilty to directly import acoustic features into the Nkululeko framework.
You can specify a file to be imported in the FEATS section:
type = ['import']
import_file = /home/.../my_features.csv
Of course the features still can be combined with other feature sets and will be assigned to training and test splits accordingly.
The feature file must be in CSV format (comma separated values) in audformat with segmented index.
Here is an example:
file,start,end,voice segments,HNR Mean (dB),F1 Mean (Hz)
/home/.../a42_1.wav,0 days,0 days 00:00:07.815875,4.13,45,7.48,