Revert to ابری

I agree it's problematic to use inconsistent transliteration systems. I don't know much about Persian but WT:Persian transliteration indicates the usage of i and â rather than ī and ā, so you should probably stick with that, and change macrons to circumflexes. I don't agree that we should leave macrons alone; if the standard is to be the usage of circumflexes, we should change the entries that way. Awhile ago I went through and corrected all the Arabic entries to use a single transliteration system.

As for ebru being an English word or not, there is a good deal of Google evidence indicating that it is (e.g. search for "ebru technique" or look at the Wikipedia articles on "ebru" and "paper marbling"). Wiktionary is descriptive rather than prescriptive, meaning it documents what people actually say rather than dictating what they should say. Since people do say "ebru" in English, it's fine to use this in English translations.

As for your comments about transliteration vs. transcription, Wiktionary somewhat misuses the term "transliteration" to refer to romanization in general, and tends to prefer a more phonetic rather than strictly written approach, which is why various Arabic letters are mapped to the same Persian letter. The idea is to help readers who aren't very familiar with the foreign script; those who are more interested in etymology are more likely to be able to handle the foreign script. Note however that there is currently a long-running discussion about transliteration vs. transcription in certain languages (e.g. Tibetan and Burmese, but also Thai, Persian, etc.) where the two differ significantly, with some proposing to use one in some circumstances and the other in other circumstances and others proposing to use the two in tandem, or to stick with the current more phonetic approach.