Thank you @EricShulman for helping . I tried this.
Here is the code I used.
<$reveal type="nomatch" state=<<qualify "$:/state/SampleReveal2">> text="show">
<$button set=<<qualify "$:/state/SampleReveal2">> setTo="show" class="mybutton">
{{$:/core/images/fold-button}}</$button>
</$reveal>
<$reveal type="match" state=<<qualify "$:/state/SampleReveal2">> text="show">
<$button set=<<qualify "$:/state/SampleReveal2">> setTo="hide" class="mybutton">
{{$:/core/images/unfold-button}}
</$button>
<$list filter="[all[current]!is[system]!is[shadow]!tag[$:/tags/SideBar]!tag[Journal]!tag[$:/tags/ViewTemplate]!tag[$:/tags/Stylesheet]!tag[tweaks]!TheBrain[no]has[page-cover]]">
<div class="rightside">
{{||Bottom Tabs for viewtemplate - without folding}}
</div>
<style>
[data-tiddler-title='{{!!title}}'] .tc-tiddler-body {
border:1px solid transparent;
width:50%;
}
[data-tiddler-title='{{!!title}}'] .rightside {
border:1px solid transparent;
width:50%;
position: absolute;
right:0;
margin-top: -35px;
}
</style>
</$list>
</$reveal>
<style>
.mybutton {float:right}
.mybutton {margin-top: -65px}
</style>
I had to use state=<<qualify "SomeTiddler">> and set=<<qualify "SomeTiddler">> for it to work. Now reveal widget of each tiddler behave independently.
But one problem is that the solution given by Saq to trigger reveal widget using keyboard shortcut here is not working now.