interbreeding

Seen mixed responses from Google searches, so I'm asking here. Anyone know if mollies and swordtails will interbreed? I've read that endlers, guppies and mollies can and will. I've read that swordtails and platties can and will. Mixed responses regarding the two groups....

So maybe it's a dumb question, but is it safe to house adult plecos of different genuses together without fear of interbreeding? For example, I have these groups - L134 - Peckoltia compta L052 - Dekeyseria sp. L333 - Hypancistrus sp. Ancistrus sp. (ABN) Right now, I have the first two housed...