Go to the original table and edit the records there. For convenience, add a button field to open the original record (time saver).
At the risk of retreading old topics, you in particular have several, several threads in this forum wherein the experts here came to the consensus that you should just use one table to begin with instead of several tables synced together. Ask yourself if you actually need multiple tables. Not prefer, need. The answer based on your post history is probably “no”.
“When will Airtable let you edit records in a synced view from the destination table?” => No one knows, and to my knowledge they have not stated they are working towards this feature. It is possible they will add this feature eventually but even that won’t save users from poor data structure.