Can SSRIs be combined with acetylcholinesterase inhibitors safely? For instance, Escitalopram (Lexapro) + Huperzine A?

I'm wondering if this combination is safe. While selective acetylcholinesterase inhibitors have no effect on serotonin levels, meaning this combination is unlikely to cause serotonin syndrome. However, escitalopram on its own has a small, slight prolongation of the QT interval, which is not dangerous at therapeutic doses. Acetylcholine may also prolong the QT interval, so drugs that increase Acetylcholine levels (like Huperzine A) may hypothetically prolong the QT interval, and together the combination may synergistically/additively prolong the QT interval, potentially increasing the risk of irregular heart rhythm (arrhythmia).

Can they be combined? Is anyone here taking them together? I've checked on drug interaction checkers and it's unclear - some say they interact, others not at all.