Oracle 18c

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create table t1 as
select 'Bran' boss,'josh' employee
from dual
union all
select 'Bran','paul' from dual
union all
select 'Bran','i-sara' from dual
union all
select 'Bran','shaun' from dual
union all
select 'Joseph','will' from dual
union all
select 'Joseph','i-alex' from dual
union all
select 'Joseph','i-vicky' from dual
union all
select 'Joseph','mary' from dual
union all
select 'Joseph','cristi' from dual;

9 rows affected

create table t2 as
select 'josh' worker,'bus' object,2 price
from dual
union all
select 'paul','car',5 from dual
union all
select 'i-sara','i-sara',null from dual
union all
select 'shaun','skate',3 from dual
union all
select 'will','football',2 from dual
union all
select 'i-alex','i-alex',null from dual
union all
select 'i-vicky','i-vicky',null from dual
union all
select 'mary','dino',6 from dual
union all
select 'cristi','bike',5 from dual;

9 rows affected

select boss, employee, object, price
      ,case when rn = 1 then 
         (select listagg(t2i.worker,',') within group (order by t2i.worker)
            from t2 t2i
            join t1 t1i 
              on t1i.employee = t2i.worker
             and t1i.boss = t1.boss
           where t2i.worker like 'i-%'
          group by t1i.boss
         ) 
       end persons
from
(select boss, employee, object, price,
   row_number() over 
   (partition by t1.boss order by null) rn
  from t1 
left join t2
  on t1.employee = t2.worker
where t1.employee not like 'i-%'
) t1
order by boss;


BOSS
EMPLOYEE
OBJECT
PRICE
PERSONS


Bran
josh
bus
2
i-sara

Bran
paul
car
5
null

Bran
shaun
skate
3
null

Joseph
will
football
2
i-alex,i-vicky

Joseph
mary
dino
6
null

Joseph
cristi
bike
5
null

BOSS	EMPLOYEE	OBJECT	PRICE	PERSONS
Bran	josh	bus	2	i-sara
Bran	paul	car	5	null
Bran	shaun	skate	3	null
Joseph	will	football	2	i-alex,i-vicky
Joseph	mary	dino	6	null
Joseph	cristi	bike	5	null