Excerpt from change request document:
The entry for Karen, Paku contained Mobwa as a dialect in the past. However, speakers of Mobwa report low inherent intelligibility with Paku. Based on low reported comprehension and separate identities, it seems that Mobwa should be considered a separate language from Paku. In addition, Mobwa is treated as a distinct variety from Paku in the linguistic literature.
Regarding Mobwa being different from Paku and from Sgaw, there is an article by Shintani (2001) in which he did lexicostatistical analysis of various Karen varieties, including Sgaw, Paku, and Mobwa. He found 79% similarity between Mobwa and Paku and put them in separate groupings. He found 74% similarity between Mobwa and Sgaw and put them in separate groupings.
The Mobwa live among the Bwe, but have to switch to Sgaw or Burmese to communicate with them. They do not have much contact with Paku people, have low understanding of Paku, and have a distinct identity from the Paku.