I made a comparison between Eclipse M6 and Eclipse M6 with batch feature installed while importing wildfly. WF is imported as maven project, maven is set to offline mode and local repository contains all needed dependencies.
I did a 4 runs with following results:
M6 was able to import WF 628,575,577,612 (in seconds) = average 598s
M6 with batch feature: 843,832,924,877 (in seconds) = average 869s