Here is one more

with t(v) as ( select '0008.22816' union all select '069.3142' )

select

[formattted] =

replace(str(parsename(t.v,2),7),' ','0') + '.' +

replace(str(parsename(t.v,1),7),' ','0'),

*

from t

Also, be aware that all presented solutions will fail or loose data if there will be more than 7 digits.

To avoid it some extra moves should be done.