How to find and replace characters in selected cells, columns or row

I googled on this issue but haven't found any solution. So maybe there is none. But I try it anyways. When I try to find and replace a character in selected cells, column or row, all the characters (which I want to replace) are selected. And not only in the table I am working on. But all the tables in the same spreadsheet.

To show you an example

I have a table (Table 1) with a column Value. For me it is necessary to have the dot "." changed into a comma ",".

In the same sheet I also have a table (2) with other info/data.

Screenshots are attached and if you look closely you will see that the columns in tables 1 and 2 have multiple entries that contain a dot ".".

Now I want to change the dot in entries in the column "Value" and therefore I select the cells in the column value.

Next step is to find & replace: Find the dot and replace with comma.

What you will notice on the screenshots is that all the dots in the whole spreadsheet are selected. So if I would now hit enter on change all, all the dots will become a comma. And that is not what I want. I only want the values made up in a (European) format I can work with.

YES !! I know I can change the European settings in the sheet into US format and then I can work with the values (calculations etc). But the everything is changed (dates, formules etc...)

AND YES !! There is a work around by hiding the columns that you don't want to change. But if you have multiple tables in your sheet it's easy to forget one column to hide and those entries will be changed unintentionally as well.

So below my screenshots that will show what I mean;

On the third screenshot you see that find & replace indicates to have found 45 entries that match what I am looking for. So if I hit change all, all the entries are changed. I don't want that, because I only want to change 9 entries; the entries in the cell in the column value.

Someone any idea?