To paste almost the same formula in each cell of the specified column

[jsv1]

I have a spreadsheet that looks like this:

   A                 | B
   ==================|==========
1  Section ABC       |
2  Foo (20.09.21)    | =REGEX($A2;"^.+\(([[:digit:]|\.]+)\)$";"$1")
3  Baaaar (25.09.21) | =REGEX($A3;"^.+\(([[:digit:]|\.]+)\)$";"$1")
4  Section XYZ       |
5  Aaa (17.09.21)    | =REGEX($A5;"^.+\(([[:digit:]|\.]+)\)$";"$1")
6  Bbbbbb (07.08.21) | =REGEX($A6;"^.+\(([[:digit:]|\.]+)\)$";"$1")

   A                 | B
   ==================|==========
1  Section ABC       |
2  Foo (20.09.21)    | 20.09.21
3  Baaaar (25.09.21) | 25.09.21
4  Section XYZ       |
5  Aaa (17.09.21)    | 17.09.21
6  Bbbbbb (07.08.21) | 07.08.21

Pasting almost the same formula in each cell in the column B is boring and errorprone.

How can I paste them automatically?

[Zizi64]

Please upload a real, ODF type sample file here.

[erAck]

Where’s the problem? Copy B2, move to B3, paste, select B5:B6, paste, …